Pay smallest balance first for momentum, or highest rate first to save the most. See both, side by side.
Simulates paying off three debts with a fixed monthly budget under both the avalanche and snowball methods, reporting the months and total interest for each.
The avalanche method directs extra payments to the highest interest rate debt first, which minimizes total interest paid and usually clears your balances soonest. The snowball method targets the smallest balance first, delivering quick wins that build motivation to keep going. Both pay the minimum on every debt while funneling any leftover budget to the priority debt. This tool runs both simulations from the same debts and budget so you can compare the trade-off directly.
Avalanche is mathematically optimal and saves the most money, so it suits people who stay motivated by numbers. Snowball can be more effective in practice for those who need the encouragement of eliminating a full debt early. The interest difference between the two is often modest when balances and rates are similar. This is an educational estimate; results assume fixed rates and payments and do not reflect fees or changing terms.
The avalanche method saves the most interest because it always attacks the highest rate first. The savings versus snowball can be small when your debts have similar balances and rates.
Paying off the smallest balance first creates an early, visible win that many people find motivating. That momentum can make it easier to stick with the plan through payoff.
In both methods the payment from a cleared debt rolls onto the next target debt, accelerating payoff. This rolling effect is what gives each strategy its power.
See the exact formula and a worked example on our methodology page.