About the debt payoff calculator
What is a debt payoff calculator?
A debt payoff calculator shows how long it will take to clear your debts and how much interest you will pay on the way. Paying only the minimums can keep you in debt for years, because a large part of each payment goes on interest. Seeing a date and a total cost makes the problem concrete, and testing an extra amount shows how much faster and cheaper repayment becomes.
This free debt payoff calculator lets you add each debt with its balance, annual interest rate (APR) and minimum monthly payment, enter any extra amount you can pay each month and choose a method: avalanche or snowball. It shows your debt-free time, total interest, payoff order and a comparison of both methods. Print the result or download CSV. It runs in your browser with no sign-up.
Avalanche or snowball?
Both methods work the same way underneath. Every debt gets its minimum payment. All remaining money goes to the priority debt. When one debt is cleared, its minimum rolls into the next. The calculator shows both methods side by side so you can see the difference in time and interest for your own debts.
- Avalanche: put extra money on the debt with the highest interest rate first. This usually costs the least interest overall.
- Snowball: put extra money on the smallest balance first. You clear debts sooner, which many people find motivating, though total interest can be higher.
How to use the calculator
- Choose your currency.
- Add each debt: a name, the current balance, the APR and the minimum monthly payment. Credit cards, personal loans, store cards and car finance all work.
- Enter any extra amount you can pay every month on top of the minimums.
- Pick a method and read the result: months to clear, total interest paid and the order debts are cleared.
- Compare both methods and download or print the plan.
How the maths works
Each month the calculator adds interest to every balance at one-twelfth of the annual rate, then pays each debt its minimum, then directs the rest of your monthly budget to the priority debt. Your monthly budget is the sum of all minimums plus your extra amount, and it stays fixed as debts clear, which is what makes the snowball effect work. The calculator stops when everything reaches zero. If your payments are too small to ever beat the interest, it tells you the debt will never clear rather than showing a misleading date.
The power of a small extra payment
Try entering an extra 25, 50 or 100 per month. Even a modest amount often shortens the repayment by months or years and reduces total interest, because every extra payment reduces the balance on which future interest is calculated. Run the calculation several times with different extra amounts to find the figure that is both affordable and effective.
Making room for extra payments
Find the money with your budget. The budget calculator shows what is left each month. The monthly budget planner helps you set aside a share of income for extra debt payments. Cutting one wants category for a few months and directing it to debt can make a visible difference. Avoid taking on new debt while repaying, and keep a small emergency buffer so a surprise bill does not push you back onto a card.
Limits to keep in mind
- Interest is calculated monthly at APR divided by twelve. Real lenders may use daily compounding, fees or promotional rates, so your real figures may differ slightly.
- Variable rates change. Re-run the calculation when they do.
- The calculator does not include late fees, new spending or penalties.
Staying motivated while paying off debt
Debt repayment is a long game, and motivation matters as much as mathematics. If the snowball method keeps you going because you clear a small balance quickly, that is a legitimate reason to choose it even when avalanche is cheaper on paper. Mark each cleared debt, celebrate in a way that costs little and keep a visible chart of the balance falling. Re-run the calculator every few months as your balances drop. Seeing the debt-free date move closer is a surprisingly effective reward.
Print, CSV and privacy
Print the payoff plan or save it as a PDF through your browser. Download CSV to keep a record. Your balances and rates are processed in your browser and are never sent to Just Plann.
Debt payoff calculator FAQ
Which method is better? Avalanche costs less in interest; snowball gives faster early wins. Choose the one you will stick with.
Does it work for a mortgage? It can model any amortising debt, but mortgages usually have specific terms, so check with your lender.
Is this financial advice? No. It is a calculator for general information. If you are struggling with debt, a free independent debt advice service in your country can help.
See your debt-free date
Enter your debts, add an extra amount and compare the two methods. The date on the screen is the one to aim for.