Debt payoff calculator: snowball vs avalanche
List every debt with its balance, APR and minimum payment, then add whatever extra you can put toward debt each month. The calculator pays every minimum, sends the extra to one target debt, and rolls each paid-off payment into the next. That's the "snowball" effect, and it works with either method.
Snowball or avalanche?
Avalanche targets the highest interest rate first and always costs the least interest. Snowball targets the smallest balance first, so you close accounts sooner, and many people find that easier to stick with. The result box shows both, so you can see what the motivation costs you in dollars.
How the math works
Each month, interest is added at APR ÷ 12, then payments are applied. If your payments don't cover the interest, the calculator tells you rather than showing a fake date.
Want the full debt payoff planner?
Spreadsheet with up to 10 debts, snowball/avalanche switch, debt-free date, charts, and printable trackers. Works in Excel and Google Sheets.
Not financial advice. These tools are for planning only. Numbers are illustrative; your lender's statements control.