Mortgage Calculator
What it answers
Your full monthly mortgage payment and total interest.
How we calculate it
We amortize the loan (price minus down payment) over the term, then add monthly property tax, insurance, and any PMI to get the full payment.
P and I = L*r/(1-(1+r)^-n) ; payment = P and I + tax/12 + insurance/12 + PMI
Assumptions
Fixed rate. PMI applies until you reach 20% equity. Taxes and insurance are estimates that vary locally.
Worked example
A $400,000 home, 20% down at 6.5%/30yr is about $2,022 principal and interest before taxes and insurance.
Open the Mortgage Calculator calculator →Home Affordability Calculator
What it answers
A comfortable purchase price based on your income, debts and down payment.
How we calculate it
We apply the lender 28/36 guideline: housing costs up to 28% of gross monthly income, and all debt up to 36%. We take the lower budget and solve for the price where principal, interest, property tax, insurance and PMI (when under 20% down) equal it.
housing budget = min(28% × income/12, 36% × income/12 − debts) ; solve price so P&I + tax + insurance + PMI = budget
Assumptions
Standard 28/36 ratios. Ignores credit score, cash reserves and HOA dues. An estimate, not a pre-approval.
Worked example
On $120,000 income with $600/mo debts and $80,000 down: the 28% limit of $2,800 applies, which supports about a $418,000 home including $141/mo PMI.
Open the Home Affordability Calculator calculator →Mortgage Refinance Calculator
What it answers
Your new payment, monthly savings, and break-even on a refinance.
How we calculate it
We re-amortize the balance at the new rate and term, compare to your current payment, and divide closing costs by the monthly savings.
savings = current payment - new payment ; break-even = costs / savings
Assumptions
Excludes escrow and taxes. A new longer term can raise total interest even when the payment drops.
Worked example
Cutting a $320,000 loan from 7% to 5.5% saves roughly $300/mo, recouping $6,000 costs in about 20 months.
Open the Mortgage Refinance Calculator calculator →15 vs 30 Year Mortgage Calculator
What it answers
How a mortgage's length changes the payment and the total interest.
How we calculate it
We price the same loan at 15, 20 and 30 years with the amortization formula, then compare total interest (payment × months − loan).
payment = P × r / (1 − (1+r)^−n) for n = 180, 240, 360
Assumptions
Same rate across terms in the comparison; real 15-year rates are usually a bit lower.
Worked example
A $360,000 loan at 6.5% pays $2,275/mo over 30 years vs $3,136/mo over 15, saving well over $250,000 in interest.
Open the 15 vs 30 Year Mortgage Calculator calculator →Mortgage Points Calculator
What it answers
Whether paying points to lower your rate pays off, via the break-even month.
How we calculate it
We compute the payment with and without points, take the monthly saving, and divide the upfront point cost by it to find the break-even month.
break-even = (points% × loan) / (payment_no_points − payment_with_points)
Assumptions
One point = 1% of the loan. Worth it only if you keep the loan past break-even. Points may be tax-deductible.
Worked example
On a $350,000 loan, 2 points cost $7,000. If they cut the payment by ~$115/mo, break-even is about 61 months, roughly five years.
Open the Mortgage Points Calculator calculator →Rent vs Buy Calculator
What it answers
Whether renting or buying leaves you with more net worth after the years you plan to stay, and the break-even year.
How we calculate it
We simulate both paths month by month. Both start with the same cash: the buyer spends it on the down payment and closing costs, the renter invests it. Each month the household with the lower housing cost invests the difference. The home appreciates, rent rises yearly, and investments grow at your return.
owner = home value × (1 − selling cost) − loan balance + investments ; renter = investments
Assumptions
Ignores taxes on investment gains, the mortgage interest deduction, the home sale exclusion and PMI. Costs to own (tax, insurance, maintenance) scale with home value.
Worked example
A $420,000 home, 20% down at 6.5%, vs. $2,200 rent, 3% appreciation and rent growth, 6% return: renting is about $39,800 ahead after 7 years; buying breaks even in year 23.
Open the Rent vs Buy Calculator calculator →Biweekly Mortgage Calculator
What it answers
How paying half your mortgage every two weeks saves interest and time.
How we calculate it
Bi-weekly means 26 half-payments a year, the equivalent of 13 monthly payments. We amortize at the bi-weekly rate and compare total interest to the monthly schedule.
bi-weekly payment = monthly ÷ 2, applied every 2 weeks (26/yr)
Assumptions
The extra payment each year goes to principal. Some lenders charge to set up bi-weekly plans.
Worked example
On a $360,000 loan at 6.5%, bi-weekly payments save roughly $105,700 in interest and clear the loan in about 24 years 2 months. Adding $190 a month to a normal payment does almost the same.
Open the Biweekly Mortgage Calculator calculator →No-Closing-Cost Mortgage Calculator
What it answers
When a no-cost loan's higher rate catches up to the closing costs of a lower-rate loan.
How we calculate it
We compute both monthly payments from the amortization formula, then divide the closing costs by the extra monthly cost of the no-cost rate.
break-even months = closing costs / (no-cost payment - low-rate payment)
Assumptions
Fixed-rate loans of the same size and term. Ignores the time value of money and taxes.
Worked example
A $350,000/30yr loan: 6.25% with $6,000 costs vs a 6.75% no-cost rate adds about $113/mo, so break-even is near 53 months.
Open the No-Closing-Cost Mortgage Calculator calculator →Mortgage Interest Deduction Calculator
What it answers
The income-tax savings from deducting mortgage interest.
How we calculate it
We multiply first-year interest (loan × rate) by your marginal tax rate, assuming you itemize.
savings = loan × rate × marginal rate
Assumptions
Assumes you itemize and the interest adds benefit beyond the standard deduction. Many filers take the standard deduction instead.
Worked example
$400,000 at 6.5% = $26,000 interest; at a 24% rate, about $6,240 saved if you itemize.
Open the Mortgage Interest Deduction Calculator calculator →Fixed vs ARM Calculator
What it answers
The fixed payment versus an ARM's starting payment and its possible adjusted payment.
How we calculate it
Each payment comes from the amortization formula at its rate. We show the fixed payment, the ARM at its intro rate, and the ARM at the rate it could reach if it adjusts up.
payment = P × r / (1 − (1+r)^−n), computed at each rate
Assumptions
Compares payments at fixed points in time. Real ARMs adjust gradually within periodic and lifetime caps.
Worked example
A $400,000/30yr loan: fixed at 6.5% ≈ $2,528/mo; ARM at 5.75% ≈ $2,334/mo (about $194 less at first); at 8.5% it would be ~$3,076/mo.
Open the Fixed vs ARM Calculator calculator →ARM Calculator
What it answers
The ARM payment before and after the rate adjusts.
How we calculate it
We compute the intro payment from the amortization formula, find the balance at the end of the intro period, then re-amortize that balance at the adjusted rate over the remaining term.
intro = P×r/(1−(1+r)^−n) ; adjusted = balance × r2/(1−(1+r2)^−(n−intro))
Assumptions
Rate holds at the intro rate through the intro period, then jumps to the adjusted rate, within the loan's caps.
Worked example
A $400,000/30yr loan: 5.75% intro ≈ $2,334/mo for 7 years; if it adjusts to 8%, the payment rises to roughly $3,000/mo.
Open the ARM Calculator calculator →Closing Costs Calculator
What it answers
The total cash needed to close on a home.
How we calculate it
We compute the down payment from the price, then closing costs as a percent of the loan, and add them.
cash = price×down% + (price − down) × closing%
Assumptions
Closing costs typically run 2-5% of the loan. Excludes prepaid escrows beyond the percentage entered.
Worked example
A $400,000 home, 20% down, 3% closing: $80,000 + $9,600 → $89,600 cash to close.
Open the Closing Costs Calculator calculator →Interest-Only Mortgage Calculator
What it answers
The low interest-only payment and the higher payment once principal repayment begins.
How we calculate it
The interest-only payment is the balance times the monthly rate. The later payment amortizes the full balance over the remaining term after the interest-only period ends.
IO = balance × r ; later = balance × r / (1 − (1+r)^−(n−io))
Assumptions
Fixed rate. Assumes the full balance remains at the end of the interest-only period (no extra principal paid).
Worked example
A $400,000 loan at 6.75%, 10-yr IO on a 30-yr term → $2,250/mo interest-only, jumping to about $3,040/mo when principal repayment starts over the remaining 20 years.
Open the Interest-Only Mortgage Calculator calculator →HELOC Calculator
What it answers
Your available home equity line of credit.
How we calculate it
We multiply home value by the lender's max combined loan-to-value, then subtract the mortgage balance.
available = value × max CLTV − mortgage balance
Assumptions
Lenders also weigh credit and income. A HELOC is secured by your home.
Worked example
$500,000 home at 85% CLTV = $425,000; less a $300,000 mortgage → $125,000 available.
Open the HELOC Calculator calculator →Loan Comparison Calculator
What it answers
The monthly payment and total interest for two loan offers, side by side.
How we calculate it
Each loan's payment comes from the amortization formula; total interest is payment × months − principal. We flag whichever has the lower total cost.
payment = P × r / (1 − (1+r)^−n) ; interest = payment × n − P
Assumptions
Same loan amount for both. Compares on rate and term; real offers should also weigh fees via APR.
Worked example
$30,000: Loan A at 6.9%/5yr ≈ $592/mo; Loan B at 5.9%/6yr ≈ $497/mo. B's lower payment stretches over more months, the tool compares total interest to name the real winner.
Open the Loan Comparison Calculator calculator →Reverse Mortgage Calculator
What it answers
A rough estimate of reverse-mortgage funds available.
How we calculate it
We apply an age-based principal limit factor to the home value, then subtract any existing mortgage that must be paid off.
available = value × principal limit factor − existing mortgage
Assumptions
A rough model. Real proceeds depend on age, rates, lending limits, and fees. HUD counseling is required.
Worked example
A $500,000 home for a 70-year-old (factor ≈ 35%) → ~$175,000 limit, less a $50,000 payoff → about $125,000.
Open the Reverse Mortgage Calculator calculator →HELOC Payment Calculator
What it answers
The interest-only and full-repayment payments on a home equity line.
How we calculate it
Interest-only is simply the balance times the monthly rate; the repayment payment uses the amortization formula over the repayment term.
interest-only = balance × r · P&I = balance × r / (1 − (1+r)^−n)
Assumptions
HELOC rates are usually variable, so payments move with rates.
Worked example
A $50,000 balance at 8.5% → $354/mo interest-only, or $620/mo to fully repay over 10 years.
Open the HELOC Payment Calculator calculator →Balloon Mortgage Calculator
What it answers
The low payment and the balloon balance due at the end.
How we calculate it
The payment is based on the longer amortization term; the balloon is the remaining balance at the shorter due date, from the amortization formula.
payment = P×r/(1−(1+r)^−n) ; balloon = P(1+r)^k − payment[((1+r)^k−1)/r]
Assumptions
Fixed rate. You must refinance, sell, or pay the balloon when it comes due.
Worked example
A $300,000 loan at 6.5% amortized over 30 years, due in 7: about $1,896/mo with a balloon near $270,000.
Open the Balloon Mortgage Calculator calculator →Retirement Calculator
What it answers
Whether your savings are on track for the retirement income you want.
How we calculate it
We work in today's dollars using a real (inflation-adjusted) return. Your savings grow with the future-value formula; the nest egg you'll need is the present value of an inflation-indexed income stream over your retirement years.
real return = (1 + return) / (1 + inflation) − 1 ; need = income × [1 − (1+real)^−years] / real
Assumptions
Contributions constant in today's dollars; savings keep earning in retirement; withdrawals keep pace with inflation.
Worked example
Wanting $5,000/mo ($60k/yr) for 25 years at a ~4.4% real return implies a nest egg near $900,000 in today's dollars.
Open the Retirement Calculator calculator →Retirement Expenses Calculator
What it answers
Your estimated annual spending in retirement, and the nest egg it implies.
How we calculate it
We sum your expense categories to an annual total and divide by 4% to show the savings needed to fund it.
annual = Σ categories ; nest egg = annual / 0.04
Assumptions
A bottom-up estimate. Healthcare tends to rise with age; work and mortgage costs often fall.
Worked example
Housing $18k + food $9k + health $8k + transport $5k + travel $8k + other $6k = $54,000/yr → about $1.35M at the 4% rule.
Open the Retirement Expenses Calculator calculator →Retirement Savings Check
What it answers
Whether your projected savings will meet your retirement income need.
How we calculate it
We grow your current balance plus monthly contributions to retirement age, then compare it to the nest egg needed = desired income ÷ withdrawal rate.
FV = PV(1+r)^n + PMT[((1+r)^n − 1)/r] ; need = income / withdrawal rate
Assumptions
Constant return, nominal dollars. The withdrawal rate (often 4%) drives the required nest egg.
Worked example
$150,000 now + $800/mo at 7% for 25 years → ~$1.24M. To fund $60,000/yr at 4% you need $1.5M → about $260,000 short.
Open the Retirement Savings Check calculator →Social Security Calculator
What it answers
A rough monthly Social Security benefit at your claiming age.
How we calculate it
We approximate average indexed monthly earnings from your average salary, apply the 2026 bend-point formula for the primary insurance amount, then adjust for claiming age.
PIA = 0.9*first 1,286 + 0.32*(up to 7,749) + 0.15*(rest) ; reduced 5/9% a month for the first 36 months early, 5/12% after ; +8% a year past 67
Assumptions
Full retirement age 67, 2026 bend points and wage base. Uses one salary figure, not your full 35-year record.
Worked example
$70,000 average earnings claiming at 67 gives roughly $2,610/mo, about $3,240 at 70 and $1,830 at 62.
Open the Social Security Calculator calculator →Retirement Inflation Calculator
What it answers
The future income needed to match today's lifestyle.
How we calculate it
We apply compound inflation to today's income need over the years to retirement.
future need = income × (1 + inflation)^years
Assumptions
Real spending changes in retirement, but this shows the erosion of a fixed dollar target.
Worked example
$60,000 today at 3% inflation over 25 years → about $125,600 needed.
Open the Retirement Inflation Calculator calculator →How Long Will My Savings Last Calculator
What it answers
How long a nest egg lasts under steady withdrawals.
How we calculate it
We grow the balance by its return each month and subtract the withdrawal, counting months until it's gone. If the withdrawal is smaller than the growth, it lasts indefinitely.
each month: balance = balance × (1 + r) − withdrawal
Assumptions
Constant return; ignores taxes and inflation.
Worked example
$500,000 drawing $3,000/mo at a 5% return lasts about 23 years 10 months.
Open the How Long Will My Savings Last Calculator calculator →Cost of Waiting Calculator
What it answers
The cost of delaying retirement savings.
How we calculate it
We compute the future value of the same contribution starting now versus after a delay, and take the difference.
cost = FV(start now) − FV(start after delay)
Assumptions
Both use the same contribution; only the start date differs.
Worked example
$500/mo at 7% for 35 years vs. waiting 5 years: waiting costs roughly $130,000+.
Open the Cost of Waiting Calculator calculator →Spending to Savings Calculator
What it answers
What daily spending could grow to if invested.
How we calculate it
We convert the daily amount to a monthly figure and compute its future value at the chosen return.
FV = (daily × 30.4)/mo compounded monthly
Assumptions
Assumes the amount is invested monthly at a constant return.
Worked example
$10/day at 7% for 30 years → about $370,000.
Open the Spending to Savings Calculator calculator →401(k) Retirement Income Calculator
What it answers
The sustainable annual income a 401(k) can produce in retirement.
How we calculate it
We project the balance to retirement, then apply your withdrawal rate to get annual (and monthly) income.
income = [PV(1+r)^n + PMT((1+r)^n−1)/r] × withdrawal rate
Assumptions
Traditional 401(k) income is taxed as ordinary income, so the figure shown is pre-tax.
Worked example
$120,000 + $1,000/mo at 7% for 25 years → ~$1.30M; at 4% that's about $52,000/yr before tax.
Open the 401(k) Retirement Income Calculator calculator →Roth vs Traditional 401(k) Calculator
What it answers
Which of Roth or traditional leaves more after-tax value at retirement.
How we calculate it
Both sides grow the same contribution. The traditional side is taxed at withdrawal and also invests the upfront tax saving; Roth is tax-free at withdrawal.
Roth = FV ; Traditional = FV(1−ret tax) + FV(tax saving invested)
Assumptions
Roth wins when your retirement tax rate ≥ today's. A fair comparison invests the traditional side's tax saving.
Worked example
$10,000/yr for 25 years at 7%: Roth ≈ tax-free balance; traditional's after-tax value plus invested savings lands near it, the gap tracks the difference between your now and later tax rates.
Open the Roth vs Traditional 401(k) Calculator calculator →Catch-Up Contribution Calculator
What it answers
How much post-50 catch-up contributions add by retirement.
How we calculate it
We take the future value of just the extra catch-up amount contributed each year to retirement.
FV = catch-up/12 × [((1+r)^n − 1)/r]
Assumptions
Isolates the catch-up amount only. IRS catch-up limits change over time.
Worked example
$8,000/yr (the 2026 limit) from 52 to 65 (13 years) at 7% → about $169,000 added, most of it growth.
Open the Catch-Up Contribution Calculator calculator →Compound Interest Calculator
What it answers
What a starting amount plus monthly deposits grows to over time.
How we calculate it
Straight application of the future-value formula with monthly compounding.
FV = PV×(1+i)^n + PMT×[(1+i)^n − 1]/i
Assumptions
Deposits at month-end, constant return, monthly compounding.
Worked example
$10,000 plus $500/mo for 20 years at 7% → $300,851, of which about $170,851 is growth.
Open the Compound Interest Calculator calculator →Savings Goal Calculator
What it answers
The monthly amount needed to reach a target by a chosen date.
How we calculate it
We rearrange the future-value formula to solve for the monthly deposit, after crediting what your current balance will grow to on its own.
PMT = (goal − PV×(1+i)^n) × i / [(1+i)^n − 1]
Assumptions
Monthly deposits and compounding, constant return.
Worked example
To reach $50,000 from $5,000 in 5 years at 4% → about $662/month.
Open the Savings Goal Calculator calculator →Millionaire Calculator
What it answers
When your savings reach a target like one million dollars.
How we calculate it
We grow your balance each month by the return and your contribution until it crosses the target, counting the months.
balance grows: b = b*(1+r) + monthly ; stop when b >= target
Assumptions
Steady return; contributions constant. Real markets vary year to year.
Worked example
$500/mo plus a $20,000 start at 7% reaches $1,000,000 in roughly 33 years.
Open the Millionaire Calculator calculator →Savings Income Calculator
What it answers
The income a savings balance provides.
How we calculate it
We multiply the balance by the chosen withdrawal rate.
income = balance × withdrawal rate
Assumptions
A 4% rate is a common long-retirement guideline; lower rates last longer.
Worked example
$500,000 at 4% → $20,000/yr (about $1,667/mo), before tax.
Open the Savings Income Calculator calculator →Double Your Money Calculator
What it answers
How long an investment takes to double at a steady return.
How we calculate it
The exact doubling time uses logarithms; the Rule of 72 is a quick mental estimate.
years to double = ln 2 ÷ ln(1 + rate) (≈ 72 ÷ rate%)
Assumptions
A constant return, in nominal terms.
Worked example
At 7%, money doubles in about 10.2 years (Rule of 72 estimates 10.3).
Open the Double Your Money Calculator calculator →Time to Reach a Savings Goal Calculator
What it answers
How long regular contributions take to reach a savings target.
How we calculate it
We grow the current balance and add each monthly contribution, counting months until it crosses the goal.
each month: balance = balance × (1 + r) + contribution
Assumptions
Monthly contributions and compounding at a constant return.
Worked example
$5,000 saved plus $500/mo at 5% reaches $50,000 in about 6 years 2 months.
Open the Time to Reach a Savings Goal Calculator calculator →Save Now vs Later Calculator
What it answers
What waiting a few years to start saving actually costs.
How we calculate it
We project the same monthly contribution to the same finish date, starting now versus after a delay, and take the difference.
cost of waiting = FV(start now) − FV(start after delay)
Assumptions
Identical contribution in both cases; the only variable is the start date.
Worked example
$300/mo at 7% for 30 years vs waiting 5 years → about $123,000 less at the end.
Open the Save Now vs Later Calculator calculator →Rate of Return Calculator
What it answers
The annualized return (CAGR) between a start and end value.
How we calculate it
We take the ratio of ending to starting value, raise it to the power of one over the years, and subtract one.
CAGR = (end / start)^(1/years) − 1
Assumptions
Assumes a single deposit and withdrawal, no contributions in between. Ignores fees and taxes.
Worked example
$10,000 → $18,000 over 7 years → (1.8)^(1/7) − 1 ≈ 8.65%/yr (80% total).
Open the Rate of Return Calculator calculator →Real Rate of Return Calculator
What it answers
Your real return after taxes and inflation.
How we calculate it
We reduce the nominal return by taxes, then adjust for inflation.
real = (1 + nominal×(1−tax))/(1 + inflation) − 1
Assumptions
A simplified model of the drag from taxes and inflation.
Worked example
7% taxed at 20% = 5.6% after tax; at 3% inflation → about 2.52% real.
Open the Real Rate of Return Calculator calculator →Effective Annual Yield Calculator
What it answers
The true annual yield (APY) from a nominal rate and compounding frequency.
How we calculate it
We compound the nominal rate at the chosen frequency over one year.
APY = (1 + rate/n)^n − 1
Assumptions
Higher frequency raises APY for the same nominal rate. Banks quote savings in APY.
Worked example
5% compounded daily → (1 + .05/365)^365 − 1 ≈ 5.127% APY.
Open the Effective Annual Yield Calculator calculator →Future Value of Savings Calculator
What it answers
What a habit of regular deposits grows into.
How we calculate it
Future value of a starting balance plus deposits at your chosen frequency, compounded at the same frequency.
FV = PV(1+i)^n + PMT × [(1+i)^n − 1] / i
Assumptions
Constant return; deposits and compounding at the chosen frequency.
Worked example
$1,000 plus $200/mo for 10 years at 6% → about $34,595.
Open the Future Value of Savings Calculator calculator →Savings Plan Calculator
What it answers
Whether projected savings meet a goal, and the monthly top-up if not.
How we calculate it
We project the balance forward, compare to the goal, and solve for the monthly contribution that would exactly reach it.
FV vs. goal ; PMT = (goal − PV(1+r)^n) × r / ((1+r)^n − 1)
Assumptions
Constant return. For near-term goals, keep savings stable to protect the deadline.
Worked example
$20,000 + $600/mo at 5% for 10 years → ~$120,000, right on a $120,000 goal.
Open the Savings Plan Calculator calculator →Saving for a Purchase Calculator
What it answers
How long to save for a purchase.
How we calculate it
We grow your balance by monthly contributions and returns until it reaches the target.
each month: balance = balance×(1+r) + contribution
Assumptions
Assumes monthly saving and compounding at the chosen rate.
Worked example
$30,000 goal, $5,000 saved, $600/mo at 4% → about 3y 5m.
Open the Saving for a Purchase Calculator calculator →Credit Card Payoff Calculator
What it answers
How long it takes to clear a card at a fixed payment, and the interest cost.
How we calculate it
We simulate the balance month by month: add interest, subtract your payment, repeat until it hits zero. If a payment is smaller than one month's interest, the balance never falls, we flag that.
each month: balance = balance + balance×r − payment
Assumptions
Fixed payment and no new charges. Real card minimums shrink as the balance drops, which stretches payoff much longer.
Worked example
$8,000 at 22.9% APR paying $300/mo → 38 months and about $3,286 in interest.
Open the Credit Card Payoff Calculator calculator →Loan Calculator
What it answers
The monthly payment on any loan and the total interest you'll pay.
How we calculate it
The amortization formula gives the base payment. If you add an extra monthly amount, we simulate the loan month by month, applying the extra straight to principal, to find the earlier payoff and interest saved.
payment = P × r / (1 − (1+r)^−n)
Assumptions
Fixed rate, equal payments. Extra payments reduce principal immediately.
Worked example
$25,000 at 8.5% over 5 years → $512.91/month, about $5,775 total interest.
Open the Loan Calculator calculator →Loan Payoff Calculator
What it answers
How long a loan takes to clear at a fixed payment, and the interest cost.
How we calculate it
We step through the balance month by month, add interest, subtract the payment, until it reaches zero.
each month: balance = balance + balance×r − payment
Assumptions
Fixed payment, no new borrowing. If the payment is below the monthly interest, the balance never falls.
Worked example
$15,000 at 9% paying $400/mo → paid off in 3 years 9 months.
Open the Loan Payoff Calculator calculator →Debt Calculator
What it answers
Your debt-to-income ratio and what it signals.
How we calculate it
We divide total monthly debt payments by gross monthly income.
DTI = (housing + other debt) / gross monthly income
Assumptions
Under 36% is comfortable; over 43% makes borrowing hard.
Worked example
$2,500 debt on $7,000 income → 35.7%, manageable.
Open the Debt Calculator calculator →Remaining Loan Balance Calculator
What it answers
The principal still owed after a number of payments.
How we calculate it
We apply the standard remaining-balance formula from the original loan, rate, term and payments made.
balance = P(1+r)^k − PMT[((1+r)^k − 1)/r]
Assumptions
Fixed rate, on-time payments. Early balances fall slowly because early payments are mostly interest.
Worked example
$250,000 at 6.5%/30yr after 60 payments → about $233,000 still owed.
Open the Remaining Loan Balance Calculator calculator →Debt Consolidation Calculator
What it answers
The new payment and total interest from consolidating debts into one loan.
How we calculate it
We simulate paying your current balances at your current payment, and compare interest to a fixed consolidation loan's payment and total interest.
new payment = P × r / (1 − (1+r)^−n) ; interest compared to current
Assumptions
A lower rate or longer term lowers the payment; a longer term can raise total interest. Assumes no new debt is added.
Worked example
$24,000 at 21% paid $700/mo vs. a 12% 4-year loan (~$632/mo), the tool shows the interest difference.
Open the Debt Consolidation Calculator calculator →Debt Restructuring Calculator
What it answers
The payment and interest after moving debt to a new loan.
How we calculate it
We compare paying the current balance at the current payment with a fixed new loan's payment and interest.
new payment = P×r/(1−(1+r)^−n)
Assumptions
A lower rate cuts interest; a longer term can add it back.
Worked example
$20,000 at 19% paid $600/mo vs. a 9% 4-year loan (~$498/mo), the tool shows the interest saved.
Open the Debt Restructuring Calculator calculator →Cash vs Financing Calculator
What it answers
Whether to pay cash or finance and invest.
How we calculate it
We compare the interest paid to finance with the growth earned by investing the cash over the same term.
compare: financing interest vs. price×(1+return)^years − price
Assumptions
Ignores taxes; assumes payments come from income, not the invested cash.
Worked example
$30,000 at 7% APR (5yr) vs. investing at 8%: financing+investing can edge ahead.
Open the Cash vs Financing Calculator calculator →Pay Off Debt or Invest Calculator
What it answers
Whether paying extra toward debt or investing it comes out ahead.
How we calculate it
We grow the same monthly amount at the debt's rate (a guaranteed return) and at the expected investment return, and compare.
compare FV(debt rate) vs. FV(investment return) over the horizon
Assumptions
Paying debt is a guaranteed return; investing is uncertain. High-rate debt usually wins.
Worked example
$500/mo for 10 years: at 18% (debt) vs. 7% (invest), paying the debt is worth far more with certainty.
Open the Pay Off Debt or Invest Calculator calculator →Balance Transfer Calculator
What it answers
Whether a 0%-intro balance transfer beats staying put, once the fee is counted.
How we calculate it
We amortize both paths at the same payment, staying at your current APR, or transferring (balance grows by the fee, low intro rate for the intro window, then your APR), and compare total interest plus the fee.
net savings = interest if you stay − (interest if you transfer + fee)
Assumptions
Same monthly payment either way; rate reverts to the current APR after the intro period.
Worked example
On $8,000 at 22.9% paying $300/mo, a 0% / 15-month transfer with a 3% fee saves roughly $2,473 net.
Open the Balance Transfer Calculator calculator →Credit Score Estimator
What it answers
An educational FICO-style score estimate from the five scoring factors.
How we calculate it
We score each factor from 0 to 1, weight them by the standard FICO shares, and map the total onto the 300 to 850 range.
score = 300 + 550*(0.35*pay + 0.30*util + 0.15*age + 0.10*mix + 0.10*new)
Assumptions
Approximates the published FICO weights. Not your real score, which uses full credit-report data.
Worked example
100% on-time, 15% utilization, 8-year history scores in the very good range.
Open the Credit Score Estimator calculator →Borrowing Power Calculator
What it answers
The loan amount a monthly payment can support.
How we calculate it
We invert the amortization formula to solve for principal from your payment, rate and term.
loan = payment × (1 − (1+r)^−n) / r
Assumptions
Shows what a payment supports mathematically; lenders also weigh income, credit and other debts.
Worked example
$450/mo at 7.5% for 5 years → about $22,470 borrowed.
Open the Borrowing Power Calculator calculator →Credit Card Minimum Payment Calculator
What it answers
The true cost of paying only a credit card's minimum.
How we calculate it
We model the common issuer minimum, 1% of the balance plus that month's interest, subject to a dollar floor, and step the balance down month by month.
minimum = max( floor, balance × 1% + balance × r )
Assumptions
No new charges. Real issuer formulas and floors vary; some cause payoff to stall for decades.
Worked example
$6,000 at 22.9% on the minimum → about 20 years 10 months and $10,362 in interest.
Open the Credit Card Minimum Payment Calculator calculator →Loan Interest Rate Calculator
What it answers
The interest rate implied by a loan amount, payment and term.
How we calculate it
We use a numerical search (bisection) to find the monthly rate that makes the amortization payment match yours, then annualize it.
solve r in: payment = loan × r / (1 − (1+r)^−n) ; APR = r × 12
Assumptions
Requires total payments to exceed the loan, or no positive rate fits.
Worked example
$20,000, $400/mo, 5 years → APR ≈ 7.42%.
Open the Loan Interest Rate Calculator calculator →Loan Payoff Date Calculator
What it answers
The payment needed to clear a loan by a target date.
How we calculate it
We solve the amortization formula for the payment given your balance, rate and chosen payoff term.
payment = balance × r / (1 − (1+r)^−n)
Assumptions
A shorter payoff raises the payment but cuts total interest. Check for prepayment penalties.
Worked example
$18,000 at 8% in 3 years → about $564/mo.
Open the Loan Payoff Date Calculator calculator →Auto Loan Calculator
What it answers
Your monthly car payment and the total cost of financing.
How we calculate it
Sales tax is applied to price minus trade-in (as in most U.S. states) and financed together with the balance, then run through the amortization formula over the loan's months.
loan = price + tax − down − trade-in ; payment = loan × r / (1 − (1+r)^−n)
Assumptions
Tax on price less trade-in. Excludes registration, dealer fees and gap insurance.
Worked example
$38,000 vehicle, $4,000 down, 6.5% tax, 7.2% APR, 60 months → $36,470 financed → $725.60/month.
Open the Auto Loan Calculator calculator →Lease vs Buy Car Calculator
What it answers
The net cost of leasing versus buying over the lease term.
How we calculate it
Buying cost is the loan payments made during the lease term minus your equity at the end of it (the car's value minus the loan balance still owed). Leasing cost is payments plus the amount due at signing.
buy = payment × months − (value − remaining balance) ; lease = lease payment × months + signing
Assumptions
Excludes insurance, maintenance, sales tax differences and lease mileage/wear charges.
Worked example
$35,000 car, 7% over 5 years, vs a $420/mo lease with $3,000 down: over 3 years leasing costs $18,120 and buying $22,429 (you'd still owe $15,479).
Open the Lease vs Buy Car Calculator calculator →0% Financing vs Rebate Calculator
What it answers
Whether dealer low-APR financing or a cash rebate costs less.
How we calculate it
We compute the total of payments for financing the full price at the dealer APR, and for financing the price minus rebate at the bank APR, then compare.
total = payment × months ; compare dealer-APR vs (price - rebate) at bank APR
Assumptions
Fixed payments over the same term. Excludes tax, fees, and promotional-rate qualification.
Worked example
A $35,000 car over 60 months: 2.9% dealer vs a $2,500 rebate at 7% bank rate, the cheaper total wins.
Open the 0% Financing vs Rebate Calculator calculator →Fuel Savings Calculator
What it answers
Annual fuel savings from a higher-MPG car.
How we calculate it
Fuel cost is miles ÷ MPG × price; we take the difference between the two vehicles.
savings = (miles/oldMPG − miles/newMPG) × price
Assumptions
Energy only; weigh against any price difference between the cars.
Worked example
13,000 mi from 22 to 38 MPG at $3.50 → about $970/yr.
Open the Fuel Savings Calculator calculator →Car Loan Early Payoff Calculator
What it answers
Time and interest saved by extra car payments.
How we calculate it
We simulate the loan at the base payment and with the extra amount, comparing payoff time and interest.
extra goes straight to principal each month
Assumptions
Confirm the lender applies extra to principal; check for prepayment penalties.
Worked example
$32,000 at 7.2%/60mo with $100/mo extra saves roughly a year and over $1,000 in interest.
Open the Car Loan Early Payoff Calculator calculator →Car Affordability Calculator
What it answers
The vehicle price that fits a monthly payment budget.
How we calculate it
We convert your budget into a maximum loan with the amortization factor, add your down payment, and back out sales tax to get the price.
loan = budget ÷ payment-factor ; price = (loan + down) ÷ (1 + tax)
Assumptions
Sales tax financed; excludes registration, fees and insurance. The optional 20/4/10 check assumes 20% down, a 48-month loan at your rate, and a payment of at most 10% of gross monthly income.
Worked example
$500/mo at 7.2% over 60 months with $3,000 down and 6.5% tax → about a $26,400 vehicle. On a $75,000 income, the 20/4/10 ceiling is about $30,000.
Open the Car Affordability Calculator calculator →Auto Refinance Calculator
What it answers
The savings from refinancing a car loan to a lower rate.
How we calculate it
We compute the remaining payments on the current loan and a new loan on the same balance, then compare payment and total cost.
old total = old payment × months left ; new total = new payment × new term
Assumptions
A longer new term lowers the payment but can raise total interest. Positive equity helps you qualify.
Worked example
$22,000 at 9.5% with 48 months left vs. 6.5%/48 → payment drops and total interest falls.
Open the Auto Refinance Calculator calculator →Lower Car Payment Calculator
What it answers
How term and down payment change a car payment.
How we calculate it
We compute the payment at your term, at a longer term, and with an extra down payment, and show the longer-term extra interest.
payment = (price − down) × r / (1 − (1+r)^−n)
Assumptions
Longer terms lower the payment but raise total interest and keep you underwater longer.
Worked example
$32,000 − $3,000 down at 7%: 60 months ≈ $574/mo, 72 months ≈ $494/mo, lower payment, more interest.
Open the Lower Car Payment Calculator calculator →Car Depreciation Calculator
What it answers
A vehicle's projected value as it depreciates.
How we calculate it
We apply a larger first-year percentage drop, then a steadier annual rate for later years.
value = price × (1 − first-year%) × (1 − annual%)^(years−1)
Assumptions
Real depreciation varies by make, model, mileage and condition. Most cars lose ~half their value in five years.
Worked example
$35,000 with a 20% first-year and 12% later drop → about $16,300 after 5 years.
Open the Car Depreciation Calculator calculator →RV Loan Calculator
What it answers
The payment and total interest on an RV loan.
How we calculate it
The amortization formula on the amount financed over the chosen (often long) term.
payment = P×r/(1−(1+r)^−n)
Assumptions
RV terms often run 10-20 years, raising total interest. Excludes tax and fees.
Worked example
$80,000 − $8,000 down at 8% over 15 years → about $688/mo.
Open the RV Loan Calculator calculator →Gas Cost Calculator
What it answers
What fuel costs you per year, month and mile.
How we calculate it
Divide annual miles by your MPG to get gallons, then multiply by the price.
annual cost = (miles ÷ MPG) × price per gallon
Assumptions
Constant driving and price; for an EV, use miles per kWh and price per kWh.
Worked example
12,000 miles at 28 MPG and $3.50/gal → $1,500/year.
Open the Gas Cost Calculator calculator →EV vs Gas Calculator
What it answers
The annual energy cost of an EV versus a gas car.
How we calculate it
Gas cost is miles ÷ MPG × price per gallon; EV cost is miles ÷ miles-per-kWh × price per kWh.
gas = miles/MPG × $/gal ; EV = miles/(mi per kWh) × $/kWh
Assumptions
Energy only, excludes purchase price, incentives, maintenance and insurance.
Worked example
12,000 mi: gas at 28 MPG and $3.50 → $1,500/yr; EV at 3.5 mi/kWh and $0.16 → ~$549/yr → about $950 saved.
Open the EV vs Gas Calculator calculator →CD Calculator
What it answers
A certificate of deposit's value at maturity and its true yield.
How we calculate it
Compound the deposit at the stated rate for the term, then report the effective APY.
value = deposit × (1 + rate/m)^(m×years) ; APY = (1 + rate/m)^m − 1
Assumptions
Held to maturity, no early-withdrawal penalty.
Worked example
$10,000 at 4.5% compounded monthly for 12 months → $10,459.40, a 4.594% APY.
Open the CD Calculator calculator →Asset Allocation Calculator
What it answers
A starting stock/bond split for your age and risk tolerance.
How we calculate it
We apply a common rule of thumb, roughly 110 minus age in stocks, adjusted up or down for risk tolerance, and bound it between 10% and 100%.
stocks% ≈ clamp(110 − age ± risk adjustment, 10, 100)
Assumptions
A general framework, not personalized advice. The stock/bond mix drives most portfolio risk and return.
Worked example
Age 40, moderate → 110 − 40 = 70% stocks / 30% bonds.
Open the Asset Allocation Calculator calculator →Taxable vs Tax-Free Return Calculator
What it answers
Whether a taxable or a tax-free yield keeps more after tax.
How we calculate it
We reduce the taxable yield by your tax rate and compare it to the tax-free yield.
after-tax taxable = taxable × (1 - tax rate) ; compare to tax-free
Assumptions
One combined tax rate. Ignores state tax, the AMT, and differences in credit risk.
Worked example
A 5% taxable yield at a 24% rate nets 3.8%, just above a 3.5% muni.
Open the Taxable vs Tax-Free Return Calculator calculator →Bond Price Calculator
What it answers
What a bond is worth given its coupon, maturity and the market yield.
How we calculate it
A bond's price is the present value of its coupon payments plus its face value at maturity, discounted at the market yield.
price = Σ coupon/(1+y)^t + face/(1+y)^n
Assumptions
Fixed coupons; the discount rate is the market yield per period.
Worked example
A $1,000, 5% bond maturing in 10 years, priced to a 6% yield → $925.61 (a discount, since yield > coupon).
Open the Bond Price Calculator calculator →Real Estate Investment Calculator
What it answers
A rental's cap rate and cash-on-cash return.
How we calculate it
Net operating income is rent × 12 × (1 − expense %). Cap rate is NOI ÷ price; cash-on-cash is annual cash flow (NOI − mortgage) ÷ cash invested.
cap rate = NOI/price ; cash-on-cash = (NOI − mortgage)/cash invested
Assumptions
Excludes appreciation, principal paydown, tax benefits, and specific vacancy assumptions. Expenses often run 35-50% of rent.
Worked example
$300,000 property, 25% down, $2,400 rent, 35% expenses → NOI ≈ $18,720; cap rate ≈ 6.2%; cash-on-cash depends on the mortgage.
Open the Real Estate Investment Calculator calculator →Compound vs Simple Interest Calculator
What it answers
What a lump sum grows to with compound interest.
How we calculate it
We compound the principal at the chosen frequency over the number of years.
FV = principal × (1 + rate/n)^(n × years)
Assumptions
No additional contributions. Time and rate drive the result far more than frequency.
Worked example
$10,000 at 7% compounded monthly for 20 years → about $40,300.
Open the Compound vs Simple Interest Calculator calculator →Options Calculator
What it answers
The Black-Scholes fair value of a call or put.
How we calculate it
We compute d1 and d2 from price, strike, time, volatility, and rate, then apply the normal distribution to price the option.
call = S*N(d1) - K*e^(-rT)*N(d2) ; put via put-call parity
Assumptions
European option on a non-dividend stock, constant volatility. Educational, not trading advice.
Worked example
A $100 stock, $105 strike, 90 days, 30% vol, 4% rate prices a call near $3.
Open the Options Calculator calculator →Risk Tolerance Quiz
What it answers
A suggested stock/bond split from your profile.
How we calculate it
We start from an age baseline (about 110 − age in stocks) and adjust for horizon and comfort, bounded 10-100%.
stocks% ≈ clamp(110 − age + horizon adj + comfort adj, 10, 100)
Assumptions
A general framework, not personalized advice.
Worked example
Age 40, mid horizon, moderate comfort → about 70% stocks / 30% bonds.
Open the Risk Tolerance Quiz calculator →Investment Return Comparison Calculator
What it answers
How much one extra point of return adds over time.
How we calculate it
We compute the future value of the same principal and contributions at two return rates and show the difference.
difference = FV(rate_high) − FV(rate_low)
Assumptions
Same contributions in both. The gap widens sharply with the horizon; fees work the same way in reverse.
Worked example
$50,000 + $500/mo for 25 years: at 6% ≈ $560k, at 7% ≈ $645k → about $85,000 more from one point.
Open the Investment Return Comparison Calculator calculator →CD Ladder Calculator
What it answers
The blended yield and per-rung amounts of a CD ladder.
How we calculate it
We split the total evenly across rungs maturing 1…N years out, interpolate each rung's rate between the short and long rate, and average them.
rate_i = short + (long − short)×i/(rungs−1) ; blended = average(rate_i)
Assumptions
Illustrative interpolation between your short and long rates. Real ladders use actual quoted CD rates.
Worked example
$25,000 over 5 rungs from 4.8% (1yr) to 4.0% (5yr) → blended ≈ 4.4%, $5,000 per rung.
Open the CD Ladder Calculator calculator →Dividend Yield Calculator
What it answers
A stock's dividend yield and the income it produces.
How we calculate it
Divide the annual dividend per share by the share price.
yield = annual dividend ÷ price ; income = dividend × shares
Assumptions
Dividends aren't guaranteed and can be cut; yield rises as price falls.
Worked example
A $1.60 dividend on a $50 share → a 3.20% yield.
Open the Dividend Yield Calculator calculator →Expense Ratio Calculator
What it answers
What a fund's expense ratio costs over time.
How we calculate it
We compute future value at the gross return and at the return minus the expense ratio, and take the difference.
cost = FV(gross) − FV(gross − fee)
Assumptions
Fees are charged on the whole balance yearly, so they compound against you.
Worked example
$50,000 + $500/mo for 30 years at 7% with a 0.75% fee costs well over $100,000.
Open the Expense Ratio Calculator calculator →Investment Loss Recovery Calculator
What it answers
The gain needed to recover a loss.
How we calculate it
We apply the recovery formula: a loss of L needs a gain of L ÷ (1 − L).
gain = loss / (1 − loss)
Assumptions
The gain is earned on a smaller balance, so it exceeds the loss.
Worked example
A 30% loss needs about a 42.9% gain to break even.
Open the Investment Loss Recovery Calculator calculator →401(k) Calculator
What it answers
Your projected 401(k) balance at retirement, split by source.
How we calculate it
We step through each year: grow the balance by your return, add your contribution (salary × your %), and add the employer match (your rate matched at their rate, capped at the match-limit % of salary). Salary rises each year by your growth rate.
each year: balance = balance×(1+return) + (yours + match)×(1 + return/2)
Assumptions
Annual contributions, mid-year timing, match capped at the stated salary percentage. Returns aren't guaranteed.
Worked example
A $45,000 balance, $85,000 salary, 8% contribution with a 50%-up-to-6% match at 7%, salary growing 3%/yr over 30 years projects to roughly $1.6M.
Open the 401(k) Calculator calculator →Salary to Hourly Calculator
What it answers
An annual salary expressed as an hourly wage, and back again.
How we calculate it
Divide annual pay by hours worked per year; multiply to reverse.
hourly = salary / (hours per week × weeks per year)
Assumptions
Gross pay before taxes; consistent hours across the year.
Worked example
$85,000 ÷ (40 × 52 = 2,080 hrs) → $40.87/hour.
Open the Salary to Hourly Calculator calculator →Bonus Tax Calculator
What it answers
The take-home amount of a bonus after withholding.
How we calculate it
We apply the 22% flat federal supplemental rate (under $1M), plus Social Security (6.2%), Medicare (1.45%), and a flat state estimate.
take-home = bonus × (1 − 22% − 6.2% − 1.45% − state%)
Assumptions
Withholding, not final tax, it settles at filing. Above $1M the federal supplemental rate is higher.
Worked example
$10,000 bonus, 4% state → about $6,635 take-home (~66%).
Open the Bonus Tax Calculator calculator →Paycheck Change Calculator
What it answers
How much a bigger pre-tax deduction actually cuts take-home pay.
How we calculate it
We reduce the deduction increase by the taxes you avoid at your combined rate.
take-home hit = increase × (1 - combined tax rate)
Assumptions
One combined rate for federal, state, and FICA. Actual withholding varies.
Worked example
A $200 pre-tax increase at a 30% rate lowers take-home by only $140.
Open the Paycheck Change Calculator calculator →401(k) Contribution Increase Calculator
What it answers
What raising your 401(k) contribution adds by retirement.
How we calculate it
We take the future value of just the extra contribution (new % − current %) × salary.
FV = extra/12 × [((1+r)^n − 1)/r]
Assumptions
Pre-tax contributions also lower current taxable income, so take-home falls by less than the full amount.
Worked example
$80,000 salary, 6%→10% adds $3,200/yr; over 25 years at 7% → about $210,000 more at retirement.
Open the 401(k) Contribution Increase Calculator calculator →401(k) Match Calculator
What it answers
The value of your employer's 401(k) match, and any you're missing.
How we calculate it
Match equals the lesser of your contribution rate or the cap, times the match rate, applied to salary.
match = min(your%, cap%) × salary × match rate
Assumptions
Contributing below the cap forfeits part of the match, free money left behind.
Worked example
$80,000 salary, 50% match up to 6%: contribute 6% → $2,400 match; contribute 3% and you leave $1,200 unclaimed.
Open the 401(k) Match Calculator calculator →457(b) Calculator
What it answers
The projected value of a 457(b).
How we calculate it
Future value of the balance plus monthly contributions at the expected return.
FV = PV(1+i)^n + PMT[((1+i)^n−1)/i]
Assumptions
457(b)s avoid the 10% early-withdrawal penalty after separation. Constant return assumed.
Worked example
$40,000 + $800/mo at 7% for 25 years → about $860,000.
Open the 457(b) Calculator calculator →403(b) Calculator
What it answers
The projected value of a 403(b).
How we calculate it
Future value of the balance plus monthly contributions at the expected return.
FV = PV(1+i)^n + PMT[((1+i)^n−1)/i]
Assumptions
A 403(b) mirrors a 401(k) in tax treatment. Constant return assumed.
Worked example
$40,000 + $800/mo at 7% for 25 years → about $860,000.
Open the 403(b) Calculator calculator →HSA Calculator
What it answers
What a health savings account could grow to, and the tax it saves.
How we calculate it
Future value of the current balance plus contributions (spread monthly) at your return; income tax saved = contributions × your tax rate; the taxable comparison applies 15% to the growth.
FV = PV(1+i)^n + PMT × [(1+i)^n − 1] / i ; tax saved = annual contribution × years × tax rate
Assumptions
Constant return; withdrawals for qualified medical costs are tax-free; payroll contributions also skip 7.65% FICA (not counted in the total).
Worked example
$5,000 plus $4,000/yr for 20 years at 6% → about $170,565, saving about $20,800 of income tax at 26%.
Open the HSA Calculator calculator →Stock Option Calculator
What it answers
The intrinsic value of your stock options.
How we calculate it
Intrinsic value is the number of options times the gain per share (current price − strike), floored at zero.
value = options × max(0, price − strike)
Assumptions
Ignores time value, taxes, vesting and exercise cost. Options below strike are 'underwater'.
Worked example
1,000 options, $12 strike, $30 price → $18/share → $18,000 intrinsic value.
Open the Stock Option Calculator calculator →Exercise Stock Options Calculator
What it answers
The cost, gain, and tax to exercise non-qualified options.
How we calculate it
We multiply options by strike for the cost, by the price-minus-strike spread for the gain, and apply your rate to the spread.
cost = shares×strike ; gain = (price-strike)×shares ; tax = gain × rate
Assumptions
NSOs taxed as ordinary income at exercise. Excludes AMT and later capital gains.
Worked example
1,000 options, $12 strike, $30 price: an $18,000 spread, about $12,240 net after 32% tax.
Open the Exercise Stock Options Calculator calculator →ESOP Calculator
What it answers
The projected value of ESOP shares.
How we calculate it
We grow the current share value at a constant rate and multiply by shares held.
value = shares × price × (1 + growth)^years
Assumptions
ESOP value is concentrated in one company. Vesting and distribution rules vary.
Worked example
500 shares at $40 growing 6% for 15 years → about $48,000.
Open the ESOP Calculator calculator →Income Tax Calculator
What it answers
Your total federal income tax and effective rate.
How we calculate it
We subtract the standard deduction plus any extra, apply the 2026 ordinary brackets to what remains, and divide by income for the effective rate.
tax = brackets(income - deduction) ; effective = tax / income
Assumptions
2026 single or MFJ brackets and standard deduction. Excludes credits, state, and payroll tax.
Worked example
$95,000 single, standard deduction, owes roughly $12,070 federal, about a 12.7% effective rate.
Open the Income Tax Calculator calculator →Estate Tax Calculator
What it answers
Federal estate tax on a large estate.
How we calculate it
We apply the 40% rate to the amount above the exemption.
tax = max(0, estate − exemption) × 40%
Assumptions
2026 exemption $15 million per person. Excludes state estate taxes and portability.
Worked example
An $8M estate is below the exemption → $0 federal estate tax.
Open the Estate Tax Calculator calculator →Tax Withholding Calculator
What it answers
Estimated federal tax withheld per paycheck.
How we calculate it
We estimate annual federal tax (standard deduction + 2026 brackets) and divide by pay periods, plus any extra.
per check = fedTax(income − standard) / periods + extra
Assumptions
2026 federal estimate. Excludes FICA, state tax, credits, and other income.
Worked example
$75,000 single, bi-weekly → roughly $295/check federal.
Open the Tax Withholding Calculator calculator →Investment Interest Expense Deduction Calculator
What it answers
Federal tax across interest, dividends, and capital gains.
How we calculate it
We tax interest at your ordinary rate and qualified dividends plus long-term gains at your capital gains rate, then sum.
tax = interest×ordinary + (dividends + gains)×cap-gains rate
Assumptions
Flat rates you supply. Excludes the 3.8% net investment income tax and state tax.
Worked example
$3,000 interest at 24% plus $14,000 gains at 15% is about $2,820 total.
Open the Investment Interest Expense Deduction Calculator calculator →Self-Employment Tax Calculator
What it answers
The Social Security and Medicare tax on self-employment profit.
How we calculate it
We take 92.35% of profit, apply 12.4% Social Security up to the wage base and 2.9% Medicare, and show the deductible half.
SE tax = 0.9235×profit × (12.4% to cap + 2.9%) ; deduction = ½ SE tax
Assumptions
2026 estimate (wage base 184,500). Separate from and in addition to income tax.
Worked example
$80,000 profit → base $73,880 → SS $9,161 + Medicare $2,143 → about $11,304 SE tax; half deductible.
Open the Self-Employment Tax Calculator calculator →Capital Gains Tax Calculator
What it answers
Federal tax on a long- or short-term capital gain.
How we calculate it
Long-term gains stack on your other taxable income and use the 0/15/20% brackets; short-term gains are taxed as ordinary income.
LT: 0/15/20% by income band ; ST: ordinary marginal rate
Assumptions
2026 federal. Excludes the 3.8% net investment income tax and state tax.
Worked example
$20,000 long-term gain on $80,000 income (single) → all at 15% → about $3,000 tax.
Open the Capital Gains Tax Calculator calculator →Taxable vs Tax-Deferred vs Tax-Free Calculator
What it answers
After-tax growth in taxable, tax-deferred, and Roth accounts.
How we calculate it
We grow the same amount in each account and apply the relevant tax: yearly for taxable, at withdrawal for deferred, and none for Roth.
Roth = amt(1-now)(1+r)^y ; deferred = amt(1+r)^y(1-later) ; taxable drag on r
Assumptions
Simple annual compounding; Roth funded with after-tax dollars. Ignores limits and fees.
Worked example
$50,000 for 25 years at 7% ends highest in the Roth when future rates hold or rise.
Open the Taxable vs Tax-Deferred vs Tax-Free Calculator calculator →Social Security Tax Calculator
What it answers
How much of Social Security is taxable.
How we calculate it
We compute provisional income (other income + half of benefits) against IRS thresholds to find the taxable share (up to 50% then 85%).
provisional = other income + 0.5×benefits ; taxable up to 50%/85% above thresholds
Assumptions
Thresholds: $25k/$34k single, $32k/$44k married. Simplified.
Worked example
$30,000 benefit + $40,000 other income (single) → most of the benefit taxable.
Open the Social Security Tax Calculator calculator →Standard Deduction vs Itemized Calculator
What it answers
Whether to itemize or take the standard deduction.
How we calculate it
We total your itemized deductions (SALT capped at $40,400 for 2026) and compare to the standard deduction.
use max(itemized, standard) ; benefit = (itemized − standard) × marginal rate
Assumptions
2026 standard deduction $16,100 single / $32,200 married. The SALT cap shrinks above $505,000 of income. Simplified.
Worked example
$12,000 mortgage interest + $9,000 SALT + $3,000 gifts = $24,000 vs. $16,100 single → itemize.
Open the Standard Deduction vs Itemized Calculator calculator →Tax-Equivalent Yield Calculator
What it answers
The taxable yield needed to match a tax-free muni.
How we calculate it
We divide the tax-free yield by one minus your combined federal-plus-state tax rate.
TEY = tax-free yield / (1 − combined tax rate)
Assumptions
The higher your bracket, the bigger the advantage. Include state rate if the bond is state-exempt.
Worked example
3.5% muni at a 24% federal rate → 3.5 / (1 − 0.24) ≈ 4.61% taxable equivalent.
Open the Tax-Equivalent Yield Calculator calculator →Tax Refund Calculator
What it answers
Your estimated federal refund or balance due.
How we calculate it
We estimate the year's federal tax (standard deduction + 2026 brackets) and subtract what's been withheld.
result = tax withheld − estimated tax
Assumptions
2026 federal estimate. Excludes credits, extra deductions, other income and state tax.
Worked example
$85,000 single, $11,000 withheld → tax ≈ $9,870 → about $1,130 refund.
Open the Tax Refund Calculator calculator →Tax Bracket Calculator
What it answers
Your marginal and effective federal income tax.
How we calculate it
We subtract the standard deduction, apply the 2026 progressive brackets, and report the marginal rate (last dollar) and effective rate (tax ÷ income).
tax = Σ (income in each bracket × bracket rate)
Assumptions
2026 federal, ordinary income only. Excludes credits, state tax and capital-gains rates.
Worked example
$90,000 single → taxable $73,900 → about $10,970 tax, 22% marginal, ~12.2% effective.
Open the Tax Bracket Calculator calculator →Life Insurance Calculator
What it answers
How much life insurance would keep your family whole.
How we calculate it
We use the DIME method, Debt, Income, Mortgage, Education, then subtract assets and coverage you already have.
need = income×years + mortgage + debts + final expenses + college − (savings + existing coverage)
Assumptions
Income replacement isn't discounted for investment growth, which builds in a modest cushion.
Worked example
$85,000 income × 15 years + $240k mortgage + $20k debts + $15k final + $100k college − $50k assets → $1.6M.
Open the Life Insurance Calculator calculator →Life Expectancy Calculator
What it answers
A rough, non-medical life expectancy estimate.
How we calculate it
We start from a population average by sex and adjust for smoking and activity level.
estimate = base(sex) + smoking adjustment + activity adjustment
Assumptions
Broad averages only. Not medical advice; individual health varies widely.
Worked example
A non-smoking, active 45-year-old female estimates in the mid-80s.
Open the Life Expectancy Calculator calculator →Funeral Cost Calculator
What it answers
The coverage needed for end-of-life costs.
How we calculate it
Add funeral, medical, legal/estate, debts and other costs, then subtract any coverage you already have.
need = (funeral + medical + legal + debts + other) − existing coverage
Assumptions
A planning estimate; funeral costs in particular vary widely.
Worked example
$9k funeral + $5k medical + $3k legal + $10k debts + $2k other → a $29,000 need.
Open the Funeral Cost Calculator calculator →Disability Insurance Calculator
What it answers
The monthly income gap if a disability stopped your paycheck.
How we calculate it
We compare essential expenses with the income you'd still have from existing coverage (a % of income) plus other sources.
gap = expenses − (income × coverage% + other income)
Assumptions
Benefits from employer-paid coverage are often taxable; self-paid policy benefits usually aren't.
Worked example
$4,000 expenses vs. 40% of $5,000 income = $2,000 → $2,000/mo gap.
Open the Disability Insurance Calculator calculator →Disability Risk Calculator
What it answers
The lifetime chance of a disability before retirement.
How we calculate it
We compound the annual disability rate over your remaining working years and take the complement.
odds = 1 - (1 - annual rate)^working years
Assumptions
Constant annual rate. Real risk depends on occupation and health.
Worked example
A 2% annual rate over 32 working years is roughly a 48% lifetime chance.
Open the Disability Risk Calculator calculator →Long-Term Care Calculator
What it answers
The projected cost of long-term care and any gap.
How we calculate it
We inflate today's annual cost to when care begins, multiply by years of care, and subtract savings.
cost = annual×(1+infl)^until × years ; gap = cost − saved
Assumptions
Costs vary widely by type and region. Medicare covers little.
Worked example
$75,000/yr today, 4% inflation, 20 years out, 3 years of care → about $493,000.
Open the Long-Term Care Calculator calculator →Lifetime Earnings Calculator
What it answers
Your projected total earnings over your remaining career.
How we calculate it
We sum each year's salary, growing it by your average annual raise.
total = Σ salary × (1 + raise)^year, for each working year
Assumptions
Nominal future dollars, not inflation-adjusted. Shows the earning power that insurance protects.
Worked example
$75,000 growing 3%/yr for 30 years → about $3.6M in total earnings.
Open the Lifetime Earnings Calculator calculator →Annuity Taxation Calculator
What it answers
The taxable and tax-free split of annuity payments.
How we calculate it
We divide the premium by expected total payments for the exclusion ratio, which is the tax-free share of each payment.
exclusion = basis / (payment × 12 × years) ; taxable = payment × (1 - exclusion)
Assumptions
Non-qualified annuity funded with after-tax dollars. Payments turn fully taxable once basis is recovered.
Worked example
$200,000 basis, $1,200/mo for 20 years excludes about 69%, so around $370 is taxable.
Open the Annuity Taxation Calculator calculator →Life Insurance Payout Calculator
What it answers
How long an insurance payout lasts.
How we calculate it
We invest the proceeds at the given return and draw down monthly until depleted.
each month: balance = balance×(1+r) − withdrawal
Assumptions
Ignores taxes and inflation. If growth exceeds the draw, it lasts indefinitely.
Worked example
$500,000 at 4% drawing $4,000/mo lasts many years; the tool shows exactly how long.
Open the Life Insurance Payout Calculator calculator →Future Value of Annuity Calculator
What it answers
The projected value of deferred annuity contributions.
How we calculate it
We compound an initial amount plus monthly contributions at a constant rate over the accumulation period.
FV = PV(1+r)^n + PMT[((1+r)^n − 1)/r]
Assumptions
Growth is tax-deferred; withdrawals are taxed as income. Fees and surrender charges vary by product.
Worked example
$25,000 + $300/mo at 5% for 20 years → about $189,000.
Open the Future Value of Annuity Calculator calculator →HDHP vs PPO Calculator
What it answers
Which health plan costs less overall.
How we calculate it
We total each plan's premium plus out-of-pocket, subtracting the HSA's tax savings on the HDHP side.
HDHP = premium + out-of-pocket − HSA×tax ; Traditional = premium + out-of-pocket
Assumptions
Simplified; real plans vary. The HSA's triple tax benefit favors the HDHP for many.
Worked example
HDHP $3,600 premium + $3,000 OOP − $720 HSA tax vs. traditional $6,000 + $1,500.
Open the HDHP vs PPO Calculator calculator →College Savings Calculator
What it answers
The monthly savings needed to fund future college costs.
How we calculate it
We inflate today's annual cost to each college year, total it, then solve for the monthly contribution given current savings and return.
cost = Σ cost_today×(1+infl)^year ; PMT solves for the goal
Assumptions
College costs have historically risen faster than general inflation. A 529 grows tax-free for qualified expenses.
Worked example
$25,000/yr today, 5% inflation, child age 5, $10,000 saved, 6% return → the tool solves the monthly amount for ~$150k projected cost.
Open the College Savings Calculator calculator →Student Loan Calculator
What it answers
The payment and total interest on a student loan, with extra-payment savings.
How we calculate it
The amortization formula gives the base payment; we simulate month by month to show payoff time and interest, including any extra payment.
payment = P × r / (1 − (1+r)^−n)
Assumptions
Standard amortization. Excludes income-driven plans and forgiveness.
Worked example
$35,000 at 6.5% over 10 years → about $397/mo and ~$12,700 interest.
Open the Student Loan Calculator calculator →Coverdell ESA Calculator
What it answers
The projected tax-free value of a Coverdell ESA.
How we calculate it
Future value of the balance plus annual contributions at the expected return.
FV = PV(1+i)^n + PMT[((1+i)^n−1)/i]
Assumptions
Capped at $2,000/yr per child, with income phase-outs. Tax-free for education.
Worked example
$5,000 + $2,000/yr at 6% for 12 years → about $45,000.
Open the Coverdell ESA Calculator calculator →529 Calculator
What it answers
The projected tax-free value of a 529 college savings plan.
How we calculate it
We compound the current balance plus monthly contributions at the expected return.
FV = PV(1+r)^n + PMT[((1+r)^n − 1)/r]
Assumptions
Growth and qualified-expense withdrawals are tax-free; non-qualified earnings face tax plus a 10% penalty.
Worked example
$8,000 + $300/mo at 6% for 13 years → about $90,000.
Open the 529 Calculator calculator →College ROI Calculator
What it answers
The net lifetime value of a degree.
How we calculate it
We multiply the annual earnings premium by years worked and subtract the degree cost.
net = premium × years − cost
Assumptions
Ignores time value of money and taxes; varies hugely by field and school.
Worked example
$100,000 cost, $22,000/yr premium over 40 years → $780,000 net, ~4.5-year payback.
Open the College ROI Calculator calculator →Parent PLUS Loan Calculator
What it answers
The payment and cost of a Parent PLUS loan.
How we calculate it
The amortization formula on the loan over the repayment term.
payment = P×r/(1−(1+r)^−n)
Assumptions
PLUS loans carry a fixed rate plus an origination fee (not included). Interest accrues in school.
Worked example
$40,000 at 9% over 10 years → about $507/mo.
Open the Parent PLUS Loan Calculator calculator →College Housing Cost Calculator
What it answers
Whether living on or off campus costs less per year.
How we calculate it
We compare annual on-campus room and board with off-campus rent, utilities, and food over the months you live there.
off-campus = (rent + utilities + food) × months ; compare to room and board
Assumptions
Excludes furniture, deposits, and commuting. Meal plans are bundled into room and board.
Worked example
$14,000 on-campus vs $1,300/mo off-campus for 9 months ($11,700) favors off campus.
Open the College Housing Cost Calculator calculator →When to Start Saving for College Calculator
What it answers
The growth lost by delaying a college fund.
How we calculate it
We grow the same monthly contribution for the full period and for the shorter period after a delay, then take the difference.
cost = FV(full years) - FV(years - delay)
Assumptions
Steady return and constant contribution. Ignores tuition inflation and taxes.
Worked example
$300/mo at 6% for 18 years vs waiting 5 years gives up several tens of thousands.
Open the When to Start Saving for College Calculator calculator →Pre-College Expenses Calculator
What it answers
The monthly saving to cover pre-college costs.
How we calculate it
We total testing, tutoring, application, and visit costs and divide by the months you have to save.
monthly = (testing + tutoring + apps + visits) / months
Assumptions
Cash saving over a short horizon. Costs vary by number of schools and test attempts.
Worked example
$5,800 of costs over 24 months is about $242/month.
Open the Pre-College Expenses Calculator calculator →Emergency Fund Calculator
What it answers
How large a cash cushion to keep, and how long to build it.
How we calculate it
Multiply your essential monthly expenses by your target months of coverage, then compare to what you've saved.
target = essential monthly expenses × months of coverage
Assumptions
Covers essentials only (housing, food, utilities, insurance, minimum debt payments).
Worked example
$4,200/mo essentials × 6 months → a $25,200 target.
Open the Emergency Fund Calculator calculator →Net Worth Calculator
What it answers
Your financial snapshot: everything you own minus everything you owe.
How we calculate it
Sum your assets, sum your debts, subtract.
net worth = total assets − total liabilities
Assumptions
Use current market values for assets and current payoff balances for debts.
Worked example
$673,000 in assets − $336,000 in debts → a $337,000 net worth.
Open the Net Worth Calculator calculator →Inflation Calculator
What it answers
The future income needed to keep today's lifestyle.
How we calculate it
We grow today's expenses by the inflation rate compounded over the years you choose.
future = expenses × (1 + inflation)^years
Assumptions
One average inflation rate. Real prices vary by category.
Worked example
$60,000 of expenses at 3% for 20 years needs about $108,000.
Open the Inflation Calculator calculator →Monthly Expense Calculator
What it answers
Your total monthly spending.
How we calculate it
We sum the spending categories to a monthly and annual total.
total = Σ category spending
Assumptions
Compare it to take-home income to find cash flow and savings rate.
Worked example
Housing $1,800 + food $800 + transport $500 + more → about $4,600/mo.
Open the Monthly Expense Calculator calculator →Extra Cash: Pay Down Debt or Invest?
What it answers
Whether extra cash builds more by paying debt or investing.
How we calculate it
We grow the same monthly amount at the debt rate and at the investment return, then compare, since paying debt earns its rate for certain.
compare FV(extra, debt rate) with FV(extra, investment return)
Assumptions
Ignores taxes, employer match, and risk. Debt payoff is a guaranteed return.
Worked example
$400/mo over 10 years favors whichever rate is higher, debt at 7% or investing at 8%.
Open the Extra Cash: Pay Down Debt or Invest? calculator →Withdrawal Calculator
What it answers
How long a portfolio lasts with withdrawals.
How we calculate it
We grow the balance by returns and subtract the monthly withdrawal until depleted.
each month: balance = balance×(1+r) − withdrawal
Assumptions
Assumes a steady return; real markets and sequence risk vary.
Worked example
$600,000 at 5% drawing $3,500/mo lasts around 25 years.
Open the Withdrawal Calculator calculator →Second Income Calculator
What it answers
What a second income adds after work costs.
How we calculate it
We subtract taxes, childcare, and commuting from the second salary to find the net benefit.
net = salary - salary×tax - childcare - commute
Assumptions
One tax rate on the added income. Excludes benefits and career growth.
Worked example
A $50,000 salary at 30% tax, $14,000 childcare, $4,000 commute nets about $17,000.
Open the Second Income Calculator calculator →Net Worth Projection Calculator
What it answers
Your net worth projected years into the future.
How we calculate it
We grow your current net worth plus annual additions at a constant rate of return.
FV = PV(1+r)^n + annual/12 × [((1+r)^n − 1)/r]
Assumptions
Nominal dollars; real markets vary. Adding more early bends the curve up most.
Worked example
$120,000 + $18,000/yr at 6% for 15 years → about $710,000.
Open the Net Worth Projection Calculator calculator →Cash Flow Calculator
What it answers
Your monthly surplus and savings rate.
How we calculate it
We subtract total spending from income and express the surplus as a share of income.
cash flow = income − spending ; savings rate = surplus / income
Assumptions
A positive figure is money to save or invest.
Worked example
$6,000 income − $4,800 spending → $1,200/mo, a 20% savings rate.
Open the Cash Flow Calculator calculator →Cash Flow Projection Calculator
What it answers
Your monthly surplus or shortfall.
How we calculate it
We subtract fixed expenses, variable spending, and planned savings from take-home income.
cash flow = income - fixed - variable - savings
Assumptions
Steady monthly figures. Average irregular bills into the month.
Worked example
$6,000 income less $3,200 fixed, $1,800 variable, $500 savings leaves a $500 surplus.
Open the Cash Flow Projection Calculator calculator →Cut Expenses Calculator
What it answers
What cutting an expense could grow to.
How we calculate it
Future value of the monthly amount invested at the chosen return.
FV = monthly × [((1+i)^n − 1)/i]
Assumptions
Assumes the freed-up amount is invested monthly.
Worked example
$150/mo at 7% for 25 years → about $121,000.
Open the Cut Expenses Calculator calculator →Value of a Dollar Calculator
What it answers
A past amount converted to today's dollars.
How we calculate it
We grow the original amount by an average inflation rate for each year between the two dates.
value = amount × (1 + rate)^(years)
Assumptions
One average rate. Official price indexes are more precise for exact years.
Worked example
$1,000 from 2000 at 2.6% average is roughly $1,950 in 2026.
Open the Value of a Dollar Calculator calculator →Cost of Living Calculator
What it answers
The salary needed in a new city for the same lifestyle.
How we calculate it
We scale your salary by the ratio of the new city's cost index to your current city's index.
needed = salary × (new index / current index)
Assumptions
A composite index; your mix may differ. Excludes state tax differences.
Worked example
$80,000 moving from index 100 to 130 needs about $104,000.
Open the Cost of Living Calculator calculator →Roth Conversion Calculator
What it answers
Whether converting to a Roth beats leaving money in a traditional IRA.
How we calculate it
We tax the conversion at today's rate (paid from savings) and grow the Roth tax-free, then compare it with keeping the IRA (taxed at your retirement rate when withdrawn) plus the same tax money kept invested.
convert = A(1+g)^y ; don't = A(1+g)^y(1 − t_later) + A·t_now·(1+g)^y ; difference = A(1+g)^y(t_later − t_now)
Assumptions
Same return on all money; taxes on the side account's growth are ignored, which slightly favors not converting.
Worked example
$100,000 at 24% now, 7% for 20 years: converting wins by $30,957 if the later rate is 32%, loses by $7,739 if it is 22%.
Open the Roth Conversion Calculator calculator →IRA Calculator
What it answers
The projected value of an IRA.
How we calculate it
Future value of the balance plus annual contributions at the expected return.
FV = PV(1+i)^n + PMT[((1+i)^n−1)/i]
Assumptions
Traditional grows tax-deferred; Roth grows tax-free. Constant return assumed.
Worked example
$30,000 + $7,500/yr at 7% for 25 years → about $678,000.
Open the IRA Calculator calculator →IRA Withdrawal Calculator
What it answers
The monthly income an IRA can pay out.
How we calculate it
We annuitize the balance to zero over the chosen years at the assumed return.
monthly = balance × r / (1 - (1 + r)^-n), r monthly, n months
Assumptions
Fixed return; ignores inflation, taxes, and RMDs. Weak early returns can shorten it.
Worked example
$600,000 at 5% over 30 years pays about $3,200/month.
Open the IRA Withdrawal Calculator calculator →Pension Lump Sum vs Annuity Calculator
What it answers
Lump sum vs. lifetime monthly pension.
How we calculate it
We grow the lump sum at your return and compare to total pension payments; we also show the payout rate.
payout rate = annual pension / lump ; compare lump×(1+r)^years vs. pension total
Assumptions
Ignores taxes, survivor benefits, and the security of guaranteed income.
Worked example
$400,000 lump vs. $2,200/mo: payout rate 6.6%; the tool compares the totals.
Open the Pension Lump Sum vs Annuity Calculator calculator →Retirement Plan Value Calculator
What it answers
Your 401(k) balance at retirement.
How we calculate it
We grow the current balance and add yearly contributions plus the employer match, compounded at your return.
FV = balance(1+r)^y + contributions and match grown monthly
Assumptions
Steady return and salary. Ignores IRS limits, fees, and future tax.
Worked example
$80,000 now plus 8% and a 4% match on $75,000 for 25 years nears $900,000.
Open the Retirement Plan Value Calculator calculator →RMD Calculator
What it answers
Your required minimum distribution this year.
How we calculate it
We divide the prior year-end balance by the IRS Uniform Lifetime Table period for your age.
RMD = balance / distribution period (age)
Assumptions
RMDs begin at 73. Roth IRAs have no lifetime RMDs.
Worked example
$500,000 at age 75 (period 24.6) → about $20,325.
Open the RMD Calculator calculator →Future RMD Calculator
What it answers
Your required minimum distributions from age 73.
How we calculate it
We divide each year's balance by the IRS Uniform Lifetime Table factor and grow the remainder at your return.
RMD = balance / lifetime factor(age)
Assumptions
Uniform Lifetime Table. Does not apply if a much-younger spouse is sole beneficiary.
Worked example
$500,000 at age 73 (factor 26.5) is a first RMD near $18,900.
Open the Future RMD Calculator calculator →Lump Sum vs Monthly Payments Calculator
What it answers
Whether a pension lump sum or monthly payments are worth more.
How we calculate it
We discount the monthly payments to present value at your rate and compare to the lump sum.
PV = payment × (1 - (1 + r)^-n) / r ; compare to lump sum
Assumptions
Fixed collection years; ignores taxes, inflation adjustments, and survivor benefits.
Worked example
A $300,000 lump sum vs $1,800/mo for 25 years at 5% favors the higher present value.
Open the Lump Sum vs Monthly Payments Calculator calculator →Maximize 401(k) Match Calculator
What it answers
The employer match you are missing.
How we calculate it
We compute the match at your contribution and at the plan ceiling, then take the gap.
missed = salary × up-to% × match rate - salary × min(your%, up-to%) × match rate
Assumptions
Reflects the match formula only. Ignores vesting and contribution limits.
Worked example
At 3% when the plan matches 50% up to 6% of $70,000, you leave about $1,050/yr unclaimed.
Open the Maximize 401(k) Match Calculator calculator →401(k) Loan Calculator
What it answers
The growth lost to a 401(k) loan.
How we calculate it
We grow the borrowed amount at the market return over the term to find the value given up.
lost growth = amount × (1 + return)^years - amount
Assumptions
Ignores taxes, repayment interest to yourself, and default risk if you leave the job.
Worked example
$20,000 out for 5 years at 8% gives up roughly $9,400 of growth.
Open the 401(k) Loan Calculator calculator →401(k) Early Withdrawal Calculator
What it answers
The tax and penalty on an early withdrawal.
How we calculate it
We apply your income tax rate plus the 10% early-withdrawal penalty.
net = amount − amount×rate − amount×10%
Assumptions
For withdrawals before 59½ from a traditional account. Excludes state tax; some exceptions apply.
Worked example
$25,000 at a 24% rate → $6,000 tax + $2,500 penalty → you keep $16,500.
Open the 401(k) Early Withdrawal Calculator calculator →Self-Employed Retirement Calculator
What it answers
Your maximum SEP-IRA or Solo 401(k) contribution.
How we calculate it
We adjust net profit for half of self-employment tax, take about 20% for the employer side, and add the employee deferral for a Solo 401(k).
employer = adjusted profit × 0.20 ; solo = employer + deferral
Assumptions
Simplified; 2026 limits. Confirm exact figures with a tax advisor.
Worked example
$120,000 net profit allows roughly $46,800 in a Solo 401(k) under 50.
Open the Self-Employed Retirement Calculator calculator →NUA Calculator
What it answers
Whether NUA or an IRA rollover costs less in tax.
How we calculate it
We tax the basis at your ordinary rate plus the appreciation at capital gains for NUA, versus all of it at ordinary rates for a rollover.
NUA tax = basis×ordinary + gain×cap-gains ; rollover = value×ordinary
Assumptions
Ignores timing, state tax, and future growth. NUA has strict eligibility rules.
Worked example
$50,000 basis, $250,000 value, a wide rate gap favors NUA.
Open the NUA Calculator calculator →Inherited IRA RMD Calculator
What it answers
The required distribution from an inherited IRA.
How we calculate it
We divide the balance by the single life expectancy factor for the beneficiary's age.
RMD = balance / single life expectancy factor
Assumptions
Most non-spouse heirs must also empty the account within 10 years. Rules vary by beneficiary.
Worked example
$200,000 for a 55-year-old (factor about 31.6) is near $6,300.
Open the Inherited IRA RMD Calculator calculator →72(t) Calculator
What it answers
Penalty-free early IRA withdrawals under Rule 72(t), by the amortization and RMD methods.
How we calculate it
Amortization spreads the balance over your exact single life expectancy (IRS table in effect since 2022) at a permitted rate for a fixed payment. The RMD method divides the balance by life expectancy each year.
amortization = balance × r / (1 − (1 + r)^−n) ; RMD = balance ÷ n ; n = single life expectancy
Assumptions
Rate up to the greater of 5% or 120% of the federal mid-term rate (Notice 2022-6). Payments continue 5 years or to 59½, whichever is later.
Worked example
$400,000 at age 52 (life expectancy 34.3) at 5%: $24,618/yr by amortization, $11,662 in year one by the RMD method.
Open the 72(t) Calculator calculator →Cafeteria Plan Tax Savings Calculator
What it answers
The tax saved by a deductible business expense.
How we calculate it
We multiply the expense by your combined marginal rate and subtract to find the net cost.
savings = expense × rate ; net = expense - savings
Assumptions
One marginal rate. Does not capture every qualified or cafeteria plan benefit.
Worked example
A $10,000 expense at 30% saves $3,000, a net cost of $7,000.
Open the Cafeteria Plan Tax Savings Calculator calculator →Startup Cost Calculator
What it answers
The total cash to launch a business and cover its runway.
How we calculate it
We add one-time costs to net monthly burn (operating cost − expected revenue) over your runway months.
total = one-time + max(0, monthly cost − revenue) × runway
Assumptions
Most startups fail by running out of cash, build in a cushion beyond the base estimate.
Worked example
$15,000 one-time + ($6,000 − $2,500)×12 → $57,000 needed.
Open the Startup Cost Calculator calculator →Billing Frequency Calculator
What it answers
Whether annual or monthly billing is worth more.
How we calculate it
We compare a discounted annual payment upfront with the present value of monthly payments reduced by churn.
annual = price×12×(1-discount) ; monthly PV sums payments net of churn
Assumptions
One year horizon. Ignores payment failures and acquisition cost.
Worked example
At $50/mo with 15% off annual, 8% capital cost, and 4% churn, the higher present value wins.
Open the Billing Frequency Calculator calculator →Business Valuation Calculator
What it answers
An estimated business value from earnings.
How we calculate it
We multiply earnings by the chosen multiple, add saleable assets, and subtract debt.
value = earnings × multiple + assets - debt
Assumptions
Multiples vary widely by industry and quality. A rough estimate, not an appraisal.
Worked example
$150,000 earnings at 3x plus $40,000 assets less $60,000 debt is about $430,000.
Open the Business Valuation Calculator calculator →Break-Even Calculator
What it answers
How many units you must sell to cover fixed costs.
How we calculate it
Each unit contributes its price minus its variable cost; break-even is the point where those contributions cover fixed costs.
break-even units = fixed costs ÷ (price − variable cost)
Assumptions
Constant price and variable cost per unit.
Worked example
$50,000 fixed, $40 price, $15 variable → margin $25 → 2,000 units.
Open the Break-Even Calculator calculator →Equipment Lease vs Buy Calculator
What it answers
Whether leasing or buying equipment costs less.
How we calculate it
We total lease payments and compare to the financed purchase cost minus expected resale value.
buy = payment×n - resale ; lease = payment×n ; compare
Assumptions
Excludes depreciation, Section 179, and maintenance. Resale value is an estimate.
Worked example
A $40,000 purchase with $12,000 resale vs $800/mo lease for 48 months, the lower total wins.
Open the Equipment Lease vs Buy Calculator calculator →Financial Ratio Calculator
What it answers
Core liquidity, leverage, and profitability ratios.
How we calculate it
We divide current assets by liabilities, debt by equity, and net income by revenue.
current = CA/CL ; debt-to-equity = debt/equity ; margin = income/revenue
Assumptions
Snapshot figures. Compare against industry norms and trends.
Worked example
$150,000 assets over $80,000 liabilities is a current ratio near 1.9.
Open the Financial Ratio Calculator calculator →Total Compensation Calculator
What it answers
The full value of a job package.
How we calculate it
We sum base salary with bonus, employer match, benefits value, and perks.
total = salary + bonus + match + benefits + perks
Assumptions
Use it to compare offers on more than salary.
Worked example
$90,000 + $9,000 + $4,500 + $8,000 + $5,000 → $116,500 total comp.
Open the Total Compensation Calculator calculator →Section 179 Calculator
What it answers
First-year tax savings from expensing equipment.
How we calculate it
We deduct the full equipment cost and multiply by your business tax rate.
savings = cost × tax rate
Assumptions
Subject to an annual limit and phase-out; equipment must be >50% business use.
Worked example
$50,000 equipment at a 24% rate → $12,000 saved, net cost $38,000.
Open the Section 179 Calculator calculator →FSA Calculator
What it answers
The tax savings from a flexible spending account.
How we calculate it
FSA contributions avoid income and FICA tax, so we multiply by the combined rate.
savings = contribution × (income tax + FICA)
Assumptions
FSAs are use-it-or-lose-it; contribute what you'll spend.
Worked example
$3,000 at a 24% + 7.65% combined rate → about $950 saved.
Open the FSA Calculator calculator →Pricing Calculator
What it answers
The price that hits your target margin.
How we calculate it
We add overhead to unit cost and divide by one minus the target margin, measured on the selling price.
price = (cost + overhead) / (1 - margin)
Assumptions
Margin is on price, not cost. Ignores demand and competitor pricing.
Worked example
A $22 total cost at a 40% margin prices at about $37.
Open the Pricing Calculator calculator →Basic Calculator
What it answers
Quick two-number arithmetic.
How we calculate it
We apply the chosen operation to the two numbers.
add, subtract, multiply, divide, power, or percent-of
Assumptions
For money questions, a specialized calculator applies the right formula.
Worked example
12 + 8 = 20; 12% of 8 = 0.96.
Open the Basic Calculator calculator →Profit Split Calculator
What it answers
Each owner's share of business profit.
How we calculate it
We distribute profit after any retained amount, then take your ownership percentage.
payout = profit × (1 − retained%) × ownership%
Assumptions
Simplified; excludes taxes and special allocations in partnership agreements.
Worked example
$250,000 profit, 20% retained, 30% owned → 30% of $200,000 = $60,000.
Open the Profit Split Calculator calculator →Refinance Break-Even Calculator
What it answers
How many months until a refinance's savings repay its closing costs.
How we calculate it
We compute the current payment over the years remaining and the new payment over the new term, then divide closing costs by the monthly saving.
break-even = closing costs / (current payment − new payment)
Assumptions
Assumes you keep the loan. A longer new term lowers the payment but can raise lifetime interest, compare total interest too.
Worked example
Refinancing $320,000 from 7.25% to 6.0% might save ~$250/mo; $5,000 in costs → break-even near 20 months.
Open the Refinance Break-Even Calculator calculator →VA IRRRL Calculator
What it answers
The savings, cost recoupment and total cost of a VA streamline refinance (IRRRL).
How we calculate it
We compute your current payment from the balance, rate and years left, the new payment with costs rolled into the loan, the months of savings needed to recoup the costs, and the total payments under each loan.
savings = current payment − new payment ; recoup months = costs ÷ savings ; compare with the VA 36-month limit
Assumptions
Costs financed into the new loan; excludes escrow, taxes and insurance.
Worked example
$320,000 with 27 years left, 6.5% to 5.5% on a new 30-year loan with $6,500 costs: saves $243.94/mo and recoups costs in 27 months.
Open the VA IRRRL Calculator calculator →Tip Calculator
What it answers
The tip and the per-person share of a bill.
How we calculate it
Tip the bill by your chosen percent, add it, then divide by the number of people.
per person = (bill × (1 + tip%)) ÷ people
Assumptions
Tip is figured on the amount you enter (pre-tax unless you include tax).
Worked example
$86.40 at 20% split 2 ways → $51.84 each.
Open the Tip Calculator calculator →Sales Tax Calculator
What it answers
Tax added to a price, or the pre-tax amount inside a total.
How we calculate it
Add mode multiplies price by the rate; extract mode divides the total by one-plus-the-rate.
add: tax = price × rate · extract: pre-tax = total ÷ (1 + rate)
Assumptions
Enter your combined state + local rate.
Worked example
$49.99 at 8.25% → $4.12 tax, $54.11 total.
Open the Sales Tax Calculator calculator →Markup Calculator
What it answers
The selling price, profit and margin from a cost and markup, plus any discount.
How we calculate it
Price is cost × (1 + markup). Margin is profit ÷ price. A discount is applied to the price.
price = cost×(1+markup) ; margin = (price−cost)/price
Assumptions
Markup is on cost; margin is on price, they differ. Discounts come straight out of margin.
Worked example
$40 cost at 50% markup → $60 price, $20 profit, 33.3% margin.
Open the Markup Calculator calculator →Percentage Calculator
What it answers
Common percentage answers: part, whole, or percent change.
How we calculate it
We apply the standard percentage relationships to the two numbers you enter.
part = whole * pct/100 ; pct = part/whole*100 ; change = (new-old)/old*100
Assumptions
Straight arithmetic. Choose the mode that matches your question.
Worked example
20% of 150 is 30; a rise from 80 to 100 is a 25% increase.
Open the Percentage Calculator calculator →Checkbook Balance Calculator
What it answers
Whether your register matches the bank.
How we calculate it
We adjust the bank balance for outstanding deposits and checks, then compare to your register.
adjusted = bank + outstanding deposits - outstanding checks ; vs register
Assumptions
Assumes all items are entered. Unrecorded fees or interest cause a difference.
Worked example
$2,500 bank + $600 deposits - $350 checks = $2,750, matching a $2,750 register.
Open the Checkbook Balance Calculator calculator →Share Certificate Calculator
What it answers
The maturity value and interest of a share certificate.
How we calculate it
We compound the deposit at the APY over the term in years.
value = deposit × (1 + APY)^(months/12)
Assumptions
APY already reflects compounding. Ignores early-withdrawal penalties.
Worked example
$15,000 at 4.5% APY for 24 months grows to about $16,380.
Open the Share Certificate Calculator calculator →Share Certificate Ladder Calculator
What it answers
The blended yield of a certificate ladder.
How we calculate it
We split the money evenly across rungs maturing 1 to N years out, interpolate each rung's rate between the short and long APY, and average them.
blended = average of interpolated rung rates ; per rung = total / rungs
Assumptions
Straight-line rate interpolation. Actual credit-union rates vary.
Worked example
$25,000 across 5 rungs from 4.8% to 4.0% blends to about 4.4%.
Open the Share Certificate Ladder Calculator calculator →Tax-Advantaged Savings Calculator
What it answers
The edge of tax-advantaged over taxable investing.
How we calculate it
The tax-advantaged account compounds at the full return; the taxable one is modeled as taxed each year, lowering the effective return.
advantage = FV(return) − FV(return×(1−tax))
Assumptions
Real taxable accounts defer some tax until sale, so the true gap is usually smaller.
Worked example
$25,000 + $500/mo for 25 years at 7%, 20% tax → tens of thousands more tax-advantaged.
Open the Tax-Advantaged Savings Calculator calculator →Tax-Deferred Investment Calculator
What it answers
The after-tax edge of tax-deferred growth.
How we calculate it
Tax-deferred grows at the full return and taxes the gain once at withdrawal; taxable is taxed each year.
deferred = amount + gain×(1−tax) ; taxable = amount×(1+return×(1−tax))^years
Assumptions
A conservative comparison; real taxable accounts defer some tax until sale.
Worked example
$50,000 for 25 years at 7%, 22% tax → tax-deferred nets more after the final tax.
Open the Tax-Deferred Investment Calculator calculator →457(b) Contribution Increase Calculator
What it answers
What raising your 457(b) contribution adds by retirement.
How we calculate it
We take the extra yearly dollars from the change in contribution percentage and grow them at your return to retirement.
extra = (new% - current%)×salary ; FV grows the monthly amount
Assumptions
Steady return; contribution stays constant. Ignores IRS limits and salary growth.
Worked example
Going 6% to 10% on $80,000 adds $3,200/yr, near $210,000 in 25 years at 7%.
Open the 457(b) Contribution Increase Calculator calculator →403(b) Contribution Increase Calculator
What it answers
What raising your 403(b) contribution adds by retirement.
How we calculate it
We take the extra yearly dollars from the change in contribution percentage and grow them at your return to retirement.
extra = (new% - current%)×salary ; FV grows the monthly amount
Assumptions
Steady return; contribution stays constant. Ignores IRS limits and salary growth.
Worked example
Going 6% to 10% on $75,000 adds $3,000/yr, near $197,000 in 25 years at 7%.
Open the 403(b) Contribution Increase Calculator calculator →Personal Tax Freedom Day Calculator
What it answers
The day you would finish paying taxes if income went to tax first.
How we calculate it
We multiply your total effective tax rate by 365 to get days worked for taxes, then count from January 1.
days = rate × 365 ; date = Jan 1 + days
Assumptions
One blended rate for all taxes. An illustration, not when any tax is actually due.
Worked example
A 28% total rate lands Tax Freedom Day in mid-April.
Open the Personal Tax Freedom Day Calculator calculator →Debt-to-Income Ratio Calculator
What it answers
The debt-to-income ratio lenders use to judge how much you can borrow.
How we calculate it
Front-end is your housing payment over gross monthly income; back-end adds all other debt payments.
back-end DTI = (housing + other debts) ÷ gross monthly income
Assumptions
Uses gross (pre-tax) income. Lenders generally want back-end ≤ 36%, up to ~43% for qualified mortgages.
Worked example
$2,100 housing + $650 other debt on $8,000 income → 34.4% back-end DTI.
Open the Debt-to-Income Ratio Calculator calculator →ROI Calculator
What it answers
The return on an investment as a percentage and a multiple.
How we calculate it
We divide the gain (final value minus cost) by the cost, and annualize it over the holding period.
ROI = (final - cost)/cost*100 ; annualized = (final/cost)^(1/years)-1
Assumptions
Excludes taxes, fees, and cash flows during the hold unless entered. Annualized assumes steady growth.
Worked example
Turning $10,000 into $15,000 is a 50% ROI, about 8.4%/yr over 5 years.
Open the ROI Calculator calculator →Simple Interest Calculator
What it answers
Interest earned on the principal only, and how compounding compares.
How we calculate it
Multiply principal, rate, and time; we also show what annual compounding would earn for contrast.
simple interest = principal × rate × time
Assumptions
No interest earned on prior interest, unlike compound interest.
Worked example
$10,000 at 5% for 3 years → $1,500 simple interest.
Open the Simple Interest Calculator calculator →Rule of 72 Calculator
What it answers
A quick estimate of how long money takes to double at a given return.
How we calculate it
Divide 72 by the rate for doubling; 114 for tripling, 144 for quadrupling. We show the exact figure alongside.
years to double ≈ 72 ÷ rate (exact = ln 2 ÷ ln(1 + rate))
Assumptions
An approximation, most accurate for rates around 6-10%.
Worked example
At 8%, 72 ÷ 8 = 9 years, the exact answer is 9.01.
Open the Rule of 72 Calculator calculator →FIRE Calculator
What it answers
The nest egg for financial independence, and how long until you reach it.
How we calculate it
Divide your annual spending by your withdrawal rate for the target, then grow current savings plus yearly contributions at your real return until they hit it.
FIRE number = annual spending ÷ withdrawal rate (4% → 25× spending)
Assumptions
Real (inflation-adjusted) return; ignores taxes and sequence-of-returns risk.
Worked example
$60,000 spending ÷ 4% → a $1.5M target; from $150k saving $30k/yr at 5% real → about 22 years.
Open the FIRE Calculator calculator →APR to APY Calculator
What it answers
The difference between a stated rate (APR) and its true yearly yield (APY).
How we calculate it
APY compounds the nominal rate over the periods in a year; we convert either direction.
APY = (1 + APR ÷ n)^n − 1, where n = compounding periods per year
Assumptions
Deposits quote APY; loans quote APR, same math, opposite incentive.
Worked example
6% APR compounded monthly → 6.17% APY.
Open the APR to APY Calculator calculator →Overtime Calculator
What it answers
Gross weekly pay once overtime is added.
How we calculate it
Regular hours at your rate, plus overtime hours at the rate times the multiplier.
weekly = rate × regular + rate × multiplier × overtime
Assumptions
Gross pay before taxes; U.S. overtime is typically 1.5× over 40 hours/week.
Worked example
$25/hr, 40 regular + 10 OT at 1.5× → $1,375/week.
Open the Overtime Calculator calculator →Paycheck Calculator
What it answers
Your estimated net pay after taxes and 401(k).
How we calculate it
Pre-tax 401(k) lowers taxable income; we apply 2026 federal brackets after the standard deduction, Social Security (6.2% to the wage base), Medicare (1.45%, plus 0.9% on high wages), and a flat state estimate.
net = gross − 401(k) − federal − 6.2%×(SS wages) − 1.45%×gross − state
Assumptions
2026 federal estimate. 401(k) contributions reduce income tax but not FICA; pre-tax health and HSA deductions reduce both. Excludes credits, local taxes, and precise W-4 withholding.
Worked example
$75,000 single, 6% 401(k), 4% state → roughly $55,300/yr take-home, about $2,125 bi-weekly.
Open the Paycheck Calculator calculator →Monte Carlo Retirement Calculator
What it answers
The chance your savings last through retirement.
How we calculate it
We run 1,000 trials, each drawing a yearly return from a normal distribution set by your average and volatility and subtracting an inflation-adjusted withdrawal; a trial succeeds if the balance stays above zero. The random numbers are seeded from your inputs, so the same inputs always give the same result.
success rate = successful trials / 1,000
Assumptions
Returns are normally distributed and independent from year to year; withdrawals grow with inflation; no spending adjustments.
Worked example
$750,000, 30 years, 6% return, 12% volatility, 3% inflation: a $30,000 (4%) withdrawal succeeds in 67% of trials; $45,000 (6%) in 19%.
Open the Monte Carlo Retirement Calculator calculator →Social Security Claiming Calculator
What it answers
Your benefit at 62, full retirement age and 70, the break-even ages, and the claiming age with the highest lifetime total.
How we calculate it
We reduce the full-retirement-age benefit for claiming early, add delayed credits for waiting, find the age where cumulative benefits from two claiming ages are equal, and total each option to your life expectancy.
early: −5/9% per month (first 36), −5/12% beyond ; delayed: +8%/yr ; break-even age = (b2·a2 − b1·a1) / (b2 − b1)
Assumptions
Ignores taxes, cost-of-living adjustments, spousal and survivor benefits, and the time value of money.
Worked example
$2,500 at FRA 67: $1,750 at 62, $3,100 at 70. 70 vs 62 breaks even at about 80 and 4 months.
Open the Social Security Claiming Calculator calculator →Retirement Withdrawal Calculator
What it answers
Your first-year monthly income and how long savings last.
How we calculate it
Income is the balance times the withdrawal rate; we then draw that amount, grow it by inflation, and grow the balance by your return until it runs out.
monthly = balance x rate / 12 ; years = until the balance depletes
Assumptions
Steady return; figures are before tax. The 4% rule is a guideline, not a guarantee.
Worked example
$800,000 at 4% is about $2,667/mo.
Open the Retirement Withdrawal Calculator calculator →Roth Conversion Optimizer
What it answers
The after-tax advantage of converting to Roth.
How we calculate it
We compare a Roth (taxed now, grows tax-free) with a traditional IRA (grows, then taxed at your retirement rate on withdrawal).
Roth = amt(1-now)(1+g)^y ; traditional = amt(1+g)^y(1-ret)
Assumptions
One growth rate; assumes the tax is paid from the account. Ignores RMDs, IRMAA, and state tax.
Worked example
$50,000, 22% now, 28% later, 15 years at 6%: about $7,200 in favor of converting.
Open the Roth Conversion Optimizer calculator →Tax-Loss Harvesting Calculator
What it answers
The tax saved by realizing investment losses.
How we calculate it
Losses offset capital gains at the capital gains rate, then up to $3,000 of ordinary income at the ordinary rate; the rest carries forward.
saved = min(loss,gain) x cg + min(loss-gain, 3000) x ord
Assumptions
The wash-sale rule can disallow the loss. Not tax advice.
Worked example
$20,000 loss, $12,000 gain at 15%/24%: $2,520 saved.
Open the Tax-Loss Harvesting Calculator calculator →Term vs Whole Life Insurance Calculator
What it answers
What investing the premium difference could build.
How we calculate it
We invest the whole-life minus term premium each year at your return for the chosen horizon.
side fund = future value of the annual premium difference
Assumptions
Ignores whole-life cash value and guarantees; investment returns are not guaranteed.
Worked example
$600 vs $5,000 premiums at 7% for 30 years: about $447,000.
Open the Term vs Whole Life Insurance Calculator calculator →IRMAA Calculator
What it answers
Your Medicare Part B and Part D surcharge.
How we calculate it
We map MAGI to a 2026 tier and return the Part B premium above the base plus the Part D surcharge.
tier by thresholds 109/137/171/205/500k single ; 218/274/342/410/750k joint
Assumptions
Based on income from two years prior; charged per person.
Worked example
$150,000 single lands in tier 2: about $240/mo surcharge ($202.90 Part B + $37.50 Part D).
Open the IRMAA Calculator calculator →Net Investment Income Tax Calculator
What it answers
The 3.8% surtax on investment income.
How we calculate it
We take 3.8% of the smaller of your net investment income and the amount your MAGI exceeds the threshold.
NIIT = 0.038 x min(NII, MAGI - threshold)
Assumptions
Threshold 200,000 single / 250,000 joint; not indexed for inflation.
Worked example
$260,000 MAGI, $40,000 income, single: $1,520.
Open the Net Investment Income Tax Calculator calculator →Asset Location Calculator
What it answers
The growth saved by sheltering income assets.
How we calculate it
We compare a yield taxed every year in a taxable account with the same yield compounding untaxed in a sheltered one.
taxable = amt(1+y(1-ord))^n ; sheltered = amt(1+y)^n
Assumptions
Shows growth before any withdrawal tax; ignores tax-efficient equities better held in taxable accounts.
Worked example
$100,000 at 4.5%, 24% rate, 20 years: about a $45,000 advantage.
Open the Asset Location Calculator calculator →Dollar-Cost Averaging Calculator
What it answers
Whether investing all at once or averaging in ends higher.
How we calculate it
We compound a lump sum for the full period and compare it to equal monthly tranches at the same steady return.
lump = amt(1+r/12)^m ; DCA = sum of (amt/m)(1+r/12)^(m-k)
Assumptions
Steady return; a smooth model cannot show real volatility.
Worked example
$60,000 over 12 months at 8%: the lump sum wins by a few hundred dollars.
Open the Dollar-Cost Averaging Calculator calculator →Debt Snowball vs Avalanche Calculator
What it answers
Which payoff method costs less, and how much sooner.
How we calculate it
We simulate both orders month by month with your fixed budget: interest accrues on each debt, every debt gets its minimum, and the rest goes to the priority debt. Paid-off minimums roll into the next debt.
avalanche = highest rate first ; snowball = smallest balance first
Assumptions
Fixed rates and payment; excludes fees and changing terms.
Worked example
$4,200 at 7%, $9,500 at 24% and $18,000 at 5.5% on $1,000/mo: both finish in 37 months; the avalanche pays $614 less interest, while the snowball clears its first debt 10 months sooner.
Open the Debt Snowball vs Avalanche Calculator calculator →Portfolio Rebalancing Calculator
What it answers
The trade needed to hit your target mix.
How we calculate it
We find the gap between your target and current stock dollars, with the opposite move in bonds.
move = total x (target% - current%)
Assumptions
Ignores taxes on sales; new contributions can rebalance without selling.
Worked example
$500,000, target 60% vs current 70%: sell $50,000 of stocks.
Open the Portfolio Rebalancing Calculator calculator →Required Rate of Return Calculator
What it answers
The annual return needed to reach a goal.
How we calculate it
We solve by iteration for the constant return that grows your current savings plus monthly contributions to the goal by the target date.
find r so future value(current, monthly, years, r) = goal
Assumptions
Steady return; flags a required return above about 10% as aggressive.
Worked example
$20,000 plus $500/mo for 20 years to $500,000 needs roughly 9-10%.
Open the Required Rate of Return Calculator calculator →S Corp Salary Calculator
What it answers
Payroll tax saved by taking distributions.
How we calculate it
We apply Social Security and Medicare tax to the salary only; the distribution portion of profit avoids it.
savings = payroll tax on all profit as salary − payroll tax on the salary ; payroll tax = 12.4% up to the wage base + 2.9%
Assumptions
Salary must be reasonable for the work; 2026 wage base is 184,500. Consult a CPA.
Worked example
$150,000 profit, $70,000 salary: about $12,240 saved.
Open the S Corp Salary Calculator calculator →QBI Deduction Calculator
What it answers
Your 20% pass-through deduction.
How we calculate it
We take the lesser of 20% of qualified business income and 20% of taxable income.
deduction = min(0.20 x QBI, 0.20 x taxable income)
Assumptions
Ignores wage/property limits and service-business phase-outs above the 2026 thresholds (201,750 single, 403,500 joint).
Worked example
$100,000 QBI, $130,000 taxable: a $20,000 deduction.
Open the QBI Deduction Calculator calculator →SEP IRA vs Solo 401(k) vs SIMPLE IRA Calculator
What it answers
Your maximum contribution under each self-employed plan.
How we calculate it
We adjust net profit for half of self-employment tax, then apply each plan's 2026 rules and take the highest.
employer ~ 20% of adjusted profit ; Solo adds 24,500 (+8,000 at 50+, +11,250 at 60-63) ; SIMPLE 17,000 + 3% match
Assumptions
2026 limits; SEP and Solo 401(k) totals cap at 72,000 plus catch-up. Estimates only.
Worked example
$120,000 profit under 50: a Solo 401(k) at about $46,800 wins (SEP about $22,300, SIMPLE about $20,300).
Open the SEP IRA vs Solo 401(k) vs SIMPLE IRA Calculator calculator →QCD Calculator
What it answers
The tax saved by giving from your IRA.
How we calculate it
A qualified charitable distribution is excluded from income and counts toward your RMD, so the saving is the amount given times your rate.
tax saved = QCD x marginal rate
Assumptions
Must be 70.5+, sent directly to a qualifying charity; you cannot also deduct it.
Worked example
$10,000 QCD at 24%: $2,400 saved.
Open the QCD Calculator calculator →Gift Tax Calculator
What it answers
How much of your gifting uses the lifetime exemption.
How we calculate it
We apply the annual exclusion per recipient; anything above it draws down the lifetime gift and estate exemption.
taxable = sum of max(0, gift - exclusion) ; exclusion = 19,000 (38,000 if split)
Assumptions
2026 figures (19,000 exclusion, 15 million lifetime exemption); a gift-tax return may still be required.
Worked example
$30,000 to 3 people, individual: $33,000 draws down the exemption.
Open the Gift Tax Calculator calculator →Cash Balance Plan Calculator
What it answers
A rough maximum cash balance contribution.
How we calculate it
We interpolate an age-based limit that rises steeply with age, capped at your income.
age-based lookup (higher with age)
Assumptions
The real figure is set by an actuary and depends on plan design; often paired with a 401(k).
Worked example
Age 52, $300,000 income is roughly $261,000.
Open the Cash Balance Plan Calculator calculator →Amortization Calculator
What it answers
Your monthly payment and the interest you pay over the life of the loan.
How we calculate it
We apply the standard amortization formula: a level monthly payment where interest is charged on the balance and the rest reduces principal.
payment = P x r / (1 − (1+r)^−n), r = rate/12, n = years x 12
Assumptions
Fixed rate and equal payments; taxes, insurance, and fees excluded.
Worked example
$300,000 at 6.5% for 30 years is about $1,896/mo and roughly $383,000 in interest.
Open the Amortization Calculator calculator →Budget Calculator
What it answers
How to split take-home pay into needs, wants, and savings.
How we calculate it
We divide your monthly take-home pay into three fixed shares.
needs = pay x 0.50 ; wants = pay x 0.30 ; savings = pay x 0.20
Assumptions
A starting framework; high-cost areas often need more than 50% for essentials.
Worked example
$5,000 take-home: $2,500 needs, $1,500 wants, $1,000 savings.
Open the Budget Calculator calculator →Property Tax Calculator
What it answers
Your annual and monthly property tax.
How we calculate it
We multiply the home's value by the effective tax rate, then divide by twelve for the escrow amount.
annual = value x rate ; monthly = annual / 12
Assumptions
Uses the effective rate; exemptions and mill-rate quirks are not modeled.
Worked example
$400,000 at 1.1% is $4,400/yr, about $367/mo.
Open the Property Tax Calculator calculator →FHA Loan Calculator
What it answers
Your full FHA payment including mortgage insurance.
How we calculate it
We finance a 1.75% upfront premium into the loan, then add principal, interest, and the annual 0.55% premium split monthly.
loan = base x 1.0175 ; payment = amortized loan + loan x 0.0055 / 12
Assumptions
Premiums as of 2025 for a 30-year loan with under 5% down; taxes and insurance excluded.
Worked example
$350,000 price, 3.5% down at 6.5%: about $2,320/mo including MIP.
Open the FHA Loan Calculator calculator →VA Loan Calculator
What it answers
Your VA payment with the funding fee and no monthly insurance.
How we calculate it
We finance the funding fee into the loan and amortize it; there is no monthly mortgage insurance.
loan = base + base x fee% ; payment = amortized loan
Assumptions
Fee varies with use and down payment; disabled veterans are often exempt.
Worked example
$350,000, 0 down, 2.15% fee at 6.25%: about $2,201/mo, no PMI.
Open the VA Loan Calculator calculator →Profit Margin Calculator
What it answers
Your profit, margin, and markup.
How we calculate it
We subtract cost from revenue, then divide profit by revenue for margin and by cost for markup.
margin = (rev − cost) / rev ; markup = (rev − cost) / cost
Assumptions
Single transaction; overhead, taxes, and fixed costs excluded.
Worked example
$10,000 revenue, $6,000 cost: $4,000 profit, 40% margin, 67% markup.
Open the Profit Margin Calculator calculator →Down Payment Calculator
What it answers
The target down payment and how long to save it.
How we calculate it
We compound your savings monthly at the entered rate and count the months until the balance reaches the goal.
goal = price x down% ; grow balance x (1+r/12) + monthly until goal
Assumptions
Steady savings rate; home prices and rates may move while you save.
Worked example
$400,000 home, 20% goal, $15,000 saved, $800/mo at 4%: roughly 6-7 years.
Open the Down Payment Calculator calculator →Rent Affordability Calculator
What it answers
A comfortable monthly rent for your income.
How we calculate it
We take the lower of 30% of gross income and the rent that keeps total debt under 36% of income.
rent = min(0.30 x income, 0.36 x income − debts)
Assumptions
Uses gross income; your comfortable figure may be lower after savings goals.
Worked example
$5,000 income, $400 debts: min($1,500, $1,400) = $1,400/mo.
Open the Rent Affordability Calculator calculator →Roth IRA Calculator
What it answers
Your projected tax-free Roth balance at retirement.
How we calculate it
We grow the current balance and level monthly contributions at your return using the future-value formula.
FV = PV(1+r)^n + PMT x ((1+r)^n − 1)/r, r = rate/12, n = years x 12
Assumptions
Steady return; 2026 limit is $7,500 ($8,600 at 50+). Qualified withdrawals are tax-free.
Worked example
$10,000 plus $7,500/yr for 30 years at 7%: about $844,000, mostly growth.
Open the Roth IRA Calculator calculator →Cash-Out Refinance Calculator
What it answers
Your new payment and loan-to-value after taking cash out.
How we calculate it
We add the cash to your current balance, check it against 80% of value, and amortize the new loan.
new loan = balance + cash ; LTV = new loan / value ; payment amortized
Assumptions
80% LTV cap on a primary home; closing costs (2-5%) excluded.
Worked example
$500,000 home, $250,000 owed, $50,000 out at 6.5%: $1,896/mo, 60% LTV.
Open the Cash-Out Refinance Calculator calculator →Capital Gains on Sale of Home Calculator
What it answers
Your taxable gain after the home-sale exclusion.
How we calculate it
We subtract selling costs and adjusted basis from the sale price, then apply the Section 121 exclusion.
taxable = max(0, sale − costs − (buy + improvements) − exclusion)
Assumptions
Exclusion is $250k single / $500k joint with 2-of-5-year use; tax shown at 15%.
Worked example
$600,000 sale, $300,000 buy, $40k improvements, $36k costs, single: $0 taxable.
Open the Capital Gains on Sale of Home Calculator calculator →Rental Property Calculator
What it answers
Monthly cash flow, net operating income, cap rate and cash-on-cash return.
How we calculate it
Rent is reduced for vacancy; operating expenses give net operating income (NOI); NOI ÷ price is the cap rate; subtracting the mortgage gives cash flow, and annual cash flow ÷ down payment is cash-on-cash.
NOI = (rent × (1 − vacancy) − expenses) × 12 ; cap = NOI ÷ price ; CoC = cash flow × 12 ÷ down payment
Assumptions
Ignores appreciation, principal paydown, closing costs and taxes.
Worked example
$300,000, 25% down at 7%, $2,400 rent, 5% vacancy, $700 expenses: cap rate 6.32%, cash flow $83/mo, 1.3% cash-on-cash.
Open the Rental Property Calculator calculator →Cap Rate Calculator
What it answers
The property's yield independent of financing.
How we calculate it
We subtract operating expenses from gross rent for net operating income, then divide by price.
cap rate = (gross rent − expenses) / price
Assumptions
Excludes the mortgage, appreciation, and one-time costs.
Worked example
$300,000 price, $30,000 rent, $9,000 expenses: $21,000 NOI, 7.0% cap.
Open the Cap Rate Calculator calculator →Home Equity Loan Calculator
What it answers
Your available equity and the loan payment.
How we calculate it
We find equity as value minus what you owe, cap borrowing at 85% combined LTV, and amortize the loan.
max = value x 0.85 − balance ; payment amortized over the term
Assumptions
85% combined LTV is typical; the loan is secured by your home.
Worked example
$500,000 home, $250,000 owed: up to $175,000 available; $50,000 at 8%/15yr is $478/mo.
Open the Home Equity Loan Calculator calculator →PMI Calculator
What it answers
Your monthly PMI, when you can cancel it, and when it ends on its own.
How we calculate it
We price PMI as a percent of the loan, then simulate scheduled payments to find when the balance reaches 80% (cancellation on request) and 78% (automatic termination) of the original price.
monthly PMI = loan × rate / 12 ; request at 80% LTV, automatic at 78%
Assumptions
Uses scheduled payments only; extra payments or appreciation end it sooner. Your actual PMI rate depends on credit and down payment.
Worked example
$350,000 price, 10% down, 0.5% PMI at 6.5%/30yr: about $131/mo, removable after about 95 months, automatic around month 109.
Open the PMI Calculator calculator →Student Loan Refinance Calculator
What it answers
The new payment and lifetime savings from refinancing.
How we calculate it
We amortize both the current and new loans and compare monthly payments and total cost.
payment = P x r / (1 − (1+r)^−n) for each loan; savings = total_old − total_new
Assumptions
Refinancing federal loans gives up income-driven repayment and forgiveness.
Worked example
$40,000 at 7%/10yr vs 5%/10yr: payment drops from ~$464 to ~$424, saving ~$5,000.
Open the Student Loan Refinance Calculator calculator →2-1 Buydown Calculator
What it answers
The payments and upfront cost of a 2-1 buydown.
How we calculate it
We amortize the loan at rate−2, rate−1, and the full rate, then total the first two years' savings.
cost = 12 x (full − year1) + 12 x (full − year2)
Assumptions
Temporary buydown funded upfront; the payment jumps to full in year three.
Worked example
$400,000 at 6.5%: year 1 ~$2,129, year 2 ~$2,398, full ~$2,528; cost about $6,350.
Open the 2-1 Buydown Calculator calculator →Coast FIRE Calculator
What it answers
The amount today that grows to your retirement goal on its own.
How we calculate it
We find the full FIRE number, then discount it to today at your real return over the years to retirement.
FIRE = spending / SWR ; coast = FIRE / (1 + real)^years
Assumptions
Uses a real (after-inflation) return; returns are not guaranteed.
Worked example
$60,000 spend at 4% SWR = $1.5M; 35 years at 5% real: coast is about $272,000.
Open the Coast FIRE Calculator calculator →NPV Calculator
What it answers
Whether an investment adds value, plus its IRR and payback.
How we calculate it
We discount each year's cash flow to today and subtract the investment for NPV, then solve for the rate that zeroes NPV.
NPV = −C0 + sum(CF / (1+d)^t) ; IRR solves NPV = 0
Assumptions
Level annual cash flows at year end; real projects vary.
Worked example
$100,000 in, $25,000/yr for 6 years at 8%: NPV about $15,600, IRR near 13%.
Open the NPV Calculator calculator →Income-Driven Repayment Calculator
What it answers
An estimated income-driven monthly payment.
How we calculate it
We find discretionary income above 150% of the poverty guideline, then take 10% of it over twelve months.
payment = max(0, AGI − 1.5 x poverty) x 0.10 / 12
Assumptions
Poverty ~$15,650 for one plus $5,500 per member; plans and rules change.
Worked example
$60,000 AGI, family of 1: discretionary about $36,500, payment near $304/mo.
Open the Income-Driven Repayment Calculator calculator →
Social Security Calculator
A rough monthly Social Security benefit at your claiming age.
We approximate average indexed monthly earnings from your average salary, apply the 2026 bend-point formula for the primary insurance amount, then adjust for claiming age.
Full retirement age 67, 2026 bend points and wage base. Uses one salary figure, not your full 35-year record.