About the Debt Snowball Calculator
This debt snowball calculator builds a month-by-month payoff plan using the snowball method: you pay the minimum on every debt, throw every spare dollar at the smallest balance, and when that debt is gone its payment rolls into the next smallest. Enter up to four debts with their balance, APR and minimum payment, plus whatever extra you can add each month.
It is built for anyone juggling credit cards, medical bills, store cards and loans who wants quick, visible wins to stay motivated. You get the order your debts will disappear, the month each one is paid off, your debt-free date, and the total interest you will pay.
The calculator also runs the same debts through the avalanche method (highest APR first) and a minimum-payments-only plan, so you can see exactly what the motivation of the snowball costs — often very little — and how much any plan beats paying minimums. Interest is charged monthly at APR ÷ 12, and your total monthly budget stays fixed until everything is paid.
With the default inputs, the months to debt-free is 2 yr 6 mo. Change any value above to recalculate instantly.
How to use the debt snowball calculator
- 1Enter each debt’s name, current balance, APR and minimum monthly payment (leave unused rows at 0).
- 2Add the extra amount you can pay every month on top of the minimums.
- 3Read your debt-free date, payoff order and total interest.
- 4Check the avalanche comparison to see what the snowball’s quick wins cost.
- 5Use the chart and table to track which debt you should be attacking this month.
Formula and method
Each month the calculator adds interest to every open debt (balance × APR ÷ 12), pays each debt its minimum, and sends whatever is left of your fixed monthly budget to the debt with the smallest balance. Because the budget never shrinks, a paid-off debt’s minimum automatically “snowballs” into the next target.
The debts are ordered by balance (smallest first; ties go to the higher APR). The same simulation is repeated with the avalanche order (highest APR first) and with minimum payments only, so the interest differences you see are like-for-like. Real card interest is usually charged on the average daily balance, so statements can differ by a few dollars.
- Budget
- Sum of all minimum payments plus your extra monthly amount
- APR
- Annual percentage rate of each debt
- extra
- Additional money you commit every month on top of minimums
Worked examples
Four debts with $250 extra a month
The monthly budget is $640 of minimums plus $250 extra = $890. The $900 medical bill is gone in month 3, the store card in month 10, the Visa in month 25 and the car loan in month 30. Total interest is about $4,102 — roughly $210 more than the avalanche order, but about $6,146 less than paying only minimums.
Big card balance, small card, and a car loan with $200 extra
Snowball targets the $1,200 card first and clears it in month 6, then the $3,500 card by month 17 and the auto loan by month 35. Total interest is about $2,757 — only around $65 more than the avalanche order for the same budget.
Aggressive payoff with $500 extra
With $1,345 a month going to debt, the gas card disappears in month 2 and the line of credit in month 8, but the 29.99% card waits until month 20. That ordering costs about $630 more interest than avalanche, yet it still saves roughly $11,621 versus paying minimums only.
Frequently asked questions
How does the debt snowball method work?+
List debts from smallest to largest balance, pay the minimum on all of them, and put every extra dollar toward the smallest. When it is paid off, add its payment to the next smallest, and repeat until you are debt-free.
Is the snowball or avalanche method better?+
Avalanche (highest APR first) almost always costs the same or less interest. Snowball gives faster early wins, which helps many people stick to the plan. This calculator shows the exact dollar difference so you can decide if the motivation is worth it.
Should I include my mortgage in the debt snowball?+
Most snowball plans, including the popular Dave Ramsey version, leave the mortgage out and focus on consumer debts first. You can include it here, but it will usually be the last debt paid because its balance is largest.
What if my minimum payment does not cover the interest?+
Then that balance grows each month unless the snowball reaches it. The calculator flags these debts; raising the extra payment or negotiating a lower rate fixes the problem fastest.
Why is my real payoff slightly different?+
Card issuers compute interest on the average daily balance and minimums change as the balance falls. This tool keeps your total monthly budget fixed and charges APR ÷ 12 monthly, which is a close approximation.
Results are estimates for educational purposes and are not financial advice. Rates, fees and terms vary — confirm with your lender or a licensed advisor before making decisions.