How to use this debt payoff calculator
- Your debts — for each one, enter a name, the current balance, the APR and the minimum monthly payment from your statement. Use Add another debt for up to six. A debt with no balance is left out.
- Extra each month — the amount you can pay on top of all the minimums combined.
- Show the plan for — choose which method’s payoff order, chart and table to display. The results always compare both.
The headline shows how long the chosen plan takes and the month you would be debt-free, counted forward from this month with the first payment next month.
How the two methods work
Both methods pay the same total amount every month: all your minimums plus the extra. They differ only in where the extra goes.
- Avalanche sends the extra to the debt with the highest APR, which cuts the most interest.
- Snowball sends it to the debt with the smallest balance, so you clear whole debts sooner.
The calculator steps through each month in this order:
Because the budget stays the same, a paid-off debt’s minimum is not spent elsewhere. It rolls over to the next target, so each payoff speeds up the one after it. The simulation stops when every balance reaches zero, or after 50 years.
Worked example
These are the calculator’s default inputs: three debts totaling $12,600 with $355 of minimum payments, plus $200 extra, for a monthly budget of $555. The APRs are illustrative.
| Debt | Balance | APR | Minimum | Paid off (avalanche) | Paid off (snowball) |
|---|---|---|---|---|---|
| Credit card | $7,400 | 22.9% | $185 | Month 26 | Month 30 |
| Store card | $1,300 | 26.9% | $45 | Month 6 | Month 6 |
| Personal loan | $3,900 | 11.5% | $125 | Month 29 | Month 16 |
In the first month, the three debts charge $207.73 of interest between them, so $347.27 of the $555 reduces what you owe.
- Avalanche pays the store card (26.9%), then the credit card (22.9%), then the personal loan. You are debt-free in 2 years 5 months and pay $3,120.33 in interest.
- Snowball pays the store card ($1,300), then the personal loan ($3,900), then the credit card. You are debt-free in 2 years 6 months and pay $3,508.51 in interest.
Avalanche saves $388.18 and one month. Snowball’s advantage is a faster second win: the personal loan is gone in month 16, while avalanche clears its second debt, the credit card, in month 26.
How much the extra amount matters
The extra payment changes far more than the choice of method. For the same three debts:
| Extra each month | Avalanche | Snowball |
|---|---|---|
| $0 | 4 years 8 months · $7,132.81 | 4 years 8 months · $7,132.81 |
| $100 | 3 years 2 months · $4,312.39 | 3 years 2 months · $4,614.31 |
| $200 | 2 years 5 months · $3,120.33 | 2 years 6 months · $3,508.51 |
| $300 | 2 years · $2,467.54 | 2 years · $2,843.49 |
With no extra, the two plans are identical here: the personal loan is cleared by its own minimum in month 38, and both methods send the freed-up $125 to the store card next. For a deeper comparison of the two approaches, read debt snowball vs. avalanche.
What this calculator does not include
- Changing minimums. Card minimums usually fall as the balance falls. The calculator keeps each minimum fixed, which is the same as continuing to pay the original amount.
- New borrowing, fees and rate changes. It assumes you stop adding to the debts and every APR stays the same.
- Daily interest. Interest is charged monthly at APR ÷ 12, so lender statements may differ slightly.
For a single card, the credit card payoff calculator also compares your plan with paying only the minimum.
Frequently asked questions
Which method should I choose?
If you will stick with either plan, avalanche costs less. If you need early wins to stay motivated, snowball may be worth its extra cost. Run both here and decide whether the difference, $388.18 in the example, is worth it to you.
Why does the calculator say my debts would never be paid off?
Your budget is no larger than the interest charged in the first month, so the total balance can’t fall. Raise the extra amount or the minimum payments until the budget is above the interest.
Should I include my mortgage or car loan?
You can. A mortgage usually has a low rate and a large balance, so it comes last under either method and mostly just lengthens the plan. It is often simpler to leave it out and keep paying it as normal. A car loan is worth including if you want to clear it early.
What if two debts have the same APR?
Avalanche then pays the smaller balance first. Snowball, when two balances are equal, pays the higher APR first.
Can I save my calculation?
Members can save any calculation, including all their debts, and reopen it later from their account. The calculator itself is free for everyone, with instant results and no sign-up. See membership.
Results are estimates for educational purposes and are not financial advice. See our disclaimer.