Debt Payoff Calculator
When you carry several debts at once, the order you attack them in changes how much interest you pay and how fast you become debt-free. This calculator runs both popular strategies — the avalanche (highest interest rate first) and the snowball (smallest balance first) — on your actual debts, so you can compare the time to clear and the total interest side by side. Add each debt's balance, interest rate, and minimum payment, set how much extra you can put toward debt each month, and switch strategies to see the difference.
| Strategy | Time to clear | Total interest |
|---|---|---|
| Avalanche (highest APR first) | 3 yr 7 mo | $4,108.13 |
| Snowball (smallest balance first) | 3 yr 7 mo | $4,479.89 |
💡 Avalanche saves $371.76 in interest versus snowball. Snowball clears your smallest balance first for an early motivational win — the right choice depends on whether you optimize for money or momentum.
How it works
Both strategies pay the minimum on every debt and throw all spare money at one target debt until it is gone, then roll that freed-up payment onto the next target — this snowballing of payments is what accelerates payoff over time.
The avalanche targets the highest interest rate first, which mathematically minimizes total interest. The snowball targets the smallest balance first, which clears individual debts faster for an early psychological win. The calculator shows both so you can see the real cost of choosing momentum over math — often it is smaller than people expect.
Each month every debt accrues interest (balance × APR ÷ 12), pays its minimum, and the surplus (extra payment plus any freed-up minimums) is applied to one target debt — the smallest balance (snowball) or the highest APR (avalanche). Cleared minimums roll into the surplus.
Worked example
Suppose you owe 6,000 at 22%, 3,000 at 15%, and 12,000 at 9%, with minimums of 150, 75, and 200, plus 300 extra each month. The avalanche clears the 22% card first and is typically debt-free a little sooner while paying noticeably less interest than the snowball, which would tackle the 3,000 balance first. Enter your own debts above to see your exact numbers and the interest difference between the two paths.
Things to watch out for
If your minimum payments plus extra cannot cover the monthly interest on your highest-rate debt, the balance grows and the plan never finishes — the calculator flags this so you can increase your payment. Promotional 0% balance-transfer offers and prepayment penalties can change the optimal order; treat those debts specially. The strategies assume fixed minimums and a constant extra payment.
Frequently asked questions
Is the snowball or avalanche method better?+
The avalanche always pays the least total interest because it kills your most expensive debt first. The snowball clears small debts faster, which keeps many people motivated. The calculator shows the interest difference so you can decide if the avalanche's savings are worth giving up the early wins.
What counts as the 'extra payment'?+
It is any amount above the combined minimum payments that you can commit each month. Even a small extra amount dramatically shortens payoff because it goes straight to principal on your target debt.
What if I can only make minimum payments?+
Set the extra payment to zero. As long as each minimum exceeds that debt's monthly interest, the debts still clear — just more slowly. If a balance keeps growing, the calculator will warn you.
Does this work in any currency?+
Yes. The math is currency-agnostic — switch your display currency at the top of the page and enter your balances in that currency.
Related calculators
Disclaimer: This calculator is for educational and informational purposes only and provides estimates, not financial advice. Interest rates, taxes, fees, and local rules vary and change over time. Confirm figures with a qualified professional before making any financial decision.
Last reviewed: 2026-06-22