What the Debt Snowball Calculator does
This debt snowball calculator builds a month-by-month payoff plan using the snowball method: pay the minimum on every debt, put any extra money towards the smallest balance, and when that debt is gone, roll its payment into the next smallest. Enter each debt's balance, APR and minimum payment plus the extra you can afford, and it gives the payoff month for every debt, the total interest and a full schedule you can download.
It also runs the same budget through the avalanche order (highest interest rate first) and a minimum-payments-only baseline, so you can see exactly what the snowball's quick wins cost or save in your own numbers rather than in a rule of thumb.
How to use it
- Add each debt with its current balance, APR and required minimum monthly payment. You can also paste a list, one debt per line.
- Enter the extra amount you can pay each month on top of all the minimums, and the month of your first payment.
- Read the debt-free date, the order in which debts are cleared and the interest compared with the avalanche order and with paying minimums only.
- Open the month-by-month schedule to see exactly what to pay on each debt, and download it as CSV to track your progress.
Reading the results
The payoff order lists debts from smallest to largest balance. Each date is the month the last payment on that debt is made if you stick to the plan.
Your monthly budget stays the same throughout - all minimums plus the extra. As debts disappear, their minimums are not spent but rolled into the next target, which is the snowball.
If the avalanche comparison shows a large saving, the snowball's motivation is costing you real money. If it is small or zero, the order matters little and the method you will stick with is the better one.
Worked example: two debts worked by hand
Debt A is 300 at 24% APR (2% a month) and debt B is 100 at 0%, each with a 50 minimum. The budget is both minimums plus 100 extra: 200 a month. The snowball targets B because it is smaller.
Month 1: A accrues 6 interest to 306; minimums take A to 256 and B to 50; the extra 100 clears B's last 50 and the remaining 50 goes to A, leaving 206. Month 2: A accrues 4.12 to 210.12; the whole 200 goes to A, leaving 10.12. Month 3: A accrues 0.20 and the final 10.32 clears it.
Total interest is 6 + 4.12 + 0.20 = 10.32 and the plan takes 3 months. Paying the 24% debt first instead (avalanche) costs 9.30 - 1.02 less - which is the trade-off the page shows for your real debts.
Formulas and scoring rules
- Monthly interest
interest = balance x APR / 12Applied to each open balance at the start of the month. Card issuers that use daily balances will differ slightly.- Monthly budget
budget = sum of all minimums + extra paymentStays fixed; freed minimums roll to the next target.- Order
smallest starting balance first; ties go to the higher APR- Each month
pay every minimum (or the remaining balance), then send what is left of the budget to the first open debt in the order, moving on when it is cleared- Limit
plans longer than 600 months (50 years) are reported as not paying offMoney shown to 2 decimals.
Why people choose the snowball
Clearing a whole debt early gives a visible result and one fewer bill to track, and for many people that momentum is what keeps a repayment plan going. The cost is that a large, high-interest debt may wait longer while interest keeps accruing.
In the example of four debts on this page, the snowball clears the first debt in month 3 but costs about 217 more interest than the avalanche over the same 29 months. Your own numbers may show a bigger or smaller difference - that is the point of running both.
Limitations: what the result does not prove
- It assumes fixed APRs, no new borrowing and that every payment is made on time. Promotional rates that end, fees and penalty rates are not modelled.
- Interest is calculated monthly at APR / 12. Lenders that charge daily interest or compound differently will produce slightly different figures.
- Minimum payments are held constant. Many credit card minimums fall as the balance falls; the plan still works if you keep paying the amount shown.
- It is a planning tool, not debt advice. If you cannot meet your minimum payments, free debt advice services can help.
Privacy: where your data goes
Everything you paste, type or drop is processed in this browser tab. It is not uploaded, logged, stored or sent to analytics. Session recording and tag-manager scripts are switched off on this page.
Standards and sources
- US CFPB - paying down debt - checked 19 Sep 2026
Frequently asked questions
How does the debt snowball method work?
List your debts from smallest to largest balance. Pay the minimum on all of them and every spare amount on the smallest. When it is paid off, add its payment to the next smallest, and so on. Each cleared debt makes the payment on the next one bigger.
Is the snowball or the avalanche better?
The avalanche always costs the same or less interest, because it targets the most expensive debt first. The snowball can be easier to stick with because debts disappear sooner. This page shows the exact difference in interest and time for your debts so you can decide.
How much extra should I pay each month?
Whatever you can sustain every month. Even a small extra amount speeds up the plan, because it compounds as debts are cleared and their minimums roll forward. Try a few amounts and watch the debt-free date move.
Should a 0% debt be in the snowball?
Include it so its minimum is counted, but be aware the snowball may target it first if it is small, even though it costs nothing. Some people move 0% debts to the end, which is what the avalanche does automatically.
Why does the plan say my debts will never be paid off?
At least one minimum payment is not larger than the interest it attracts, or the whole budget barely covers the interest, so the balance does not fall within 50 years. Increase the extra payment or ask the lender about a lower rate or a repayment arrangement.
Can I print or export my snowball plan?
Yes. Download the month-by-month schedule as CSV to open in a spreadsheet, copy a summary of the payoff dates, or print the page. Everything is calculated in your browser; the debts you enter are not stored or sent anywhere.
Last reviewed by the A2Z.Tools team against the sources listed above.
