Free US finance tools
Debt Snowball vs. Avalanche Calculator
Compare two ways to pay off your debts using the same monthly budget. See where your payments go, how long repayment takes and how much interest each approach costs.
How the comparison works
Each month starts with interest at APR ÷ 12. We pay each active debt its entered minimum, then apply the remaining fixed budget to the smallest balance (snowball) or highest APR (avalanche). Unused money moves to the next debt in the same month. Interest and payments are rounded to cents.
For example, two 0% debts of $50 and $100 with $50 minimums have a $100 total monthly budget. They take two months, not one: $100 in month one and $50 in month two.
Which method should I choose?
Avalanche prioritizes expensive debt; snowball prioritizes clearing smaller accounts. The result compares the numbers under your inputs, not your motivation or ability to maintain payments. A tie means neither method saves interest in this model.
Important limits
We assume no new purchases, fees, changing rates, promotional periods or prepayment penalties. Real credit cards commonly accrue interest daily and change minimum payments. This is a fixed-payment monthly model, not a lender payoff quote. If a balance remains after 600 months, we show it as unpaid rather than inventing a debt-free date.
Need to plan a home loan instead? Try the mortgage and extra-payment calculator.
Sources and review
Calculation rules checked September 20, 2026. These tools are educational estimates, not personal financial or tax advice.
Found a problem? Report it. See our calculation and correction policy.