Debt Repayment Calculator
Work out your monthly payment, total interest and debt-free date, then see how extra payments or a snowball or avalanche plan can cut the cost.
What Is a Debt Repayment Calculator?
A debt repayment calculator shows exactly what a loan or credit card balance will cost you. Enter the balance, the interest rate and the time you want to take, and it works out your monthly payment, the total interest you will pay and the month you become debt-free. It also shows how much you save by paying a little extra each month.
How to Use This Calculator
- Pick Single Loan for one balance, or Multiple Debts to compare payoff strategies across up to five debts.
- Enter your balance, annual interest rate (APR) and term. For multiple debts, enter each balance, rate and minimum payment.
- Add an optional extra monthly amount. Even a small amount can shorten payoff by months or years.
- Press Calculate to see your payment, total interest, payoff date, a balance chart and a year-by-year schedule.
Worked Example
A $50,000 loan at 10% APR over 10 years has a monthly payment of about $660.75. Over 120 payments you repay roughly $79,290, of which about $29,290 is interest. If you add $100 a month, you clear the loan in about 8 years and save roughly $6,500 in interest.
How the Payment Is Calculated
For a fixed-rate installment loan, the payment is Balance x r / (1 – (1 + r)^-n), where r is the monthly rate (APR divided by 12) and n is the number of monthly payments. Each month, interest is the remaining balance times r. The rest of your payment reduces the principal, so the interest portion shrinks over time. With a 0% rate the payment is simply the balance divided by the number of months.
Snowball vs Avalanche
| Method | How it works | Best for |
|---|---|---|
| Avalanche | Pay extra toward the highest interest rate first | Paying the least total interest |
| Snowball | Pay extra toward the smallest balance first | Quick wins and staying motivated |
| Minimums only | Pay only the required minimums | Baseline for comparison |
In both methods you keep paying the same total each month. When one debt is cleared, its payment rolls into the next one. The multiple debts tab simulates all three so you can compare the real cost and timeline.
Useful Facts About Debt
| Topic | What to know |
|---|---|
| Credit card APRs | Often above 20%, so they are usually the first target for extra payments |
| Student loan interest deduction | Up to $2,500 a year of interest may be deductible, subject to income limits |
| Debt-to-income ratio | Lenders often prefer total monthly debt payments under about 36% to 43% of gross income |
| Extra payments | Ask your lender to apply extra money to principal, not to future payments |
Why Use This Calculator
It is free, needs no sign-up and runs in your browser, so your numbers are never sent anywhere. You can test different terms and extra amounts in seconds, and see the effect on both your monthly budget and your total cost before committing to a loan or a payoff plan.
Tips to Pay Off Debt Faster
- Pay more than the minimum, even if it is only $25 a month.
- Make a payment every two weeks instead of monthly, which adds one extra payment a year.
- Consider refinancing or a balance transfer if you can get a meaningfully lower rate, after checking fees.
- Put windfalls such as tax refunds or bonuses straight onto your highest-cost debt.
- Build a small emergency fund first so surprises do not go back on a credit card.
Frequently Asked Questions
How do I calculate my monthly loan payment?
Use the amortization formula with your balance, monthly interest rate and number of payments, or enter the details into this calculator and it does it for you.
Is the snowball or avalanche method better?
The avalanche method normally costs less interest. The snowball method clears small debts sooner, which some people find easier to stick with. Compare both on the Multiple Debts tab.
Does paying extra really save money?
Yes. Extra money goes straight to principal, which lowers the interest charged every month after that and shortens the payoff time.
Are the results exact?
They are accurate estimates for fixed-rate debts with monthly compounding. Variable rates, fees, promotional rates and lender rounding can change real figures slightly.
Is my information stored?
No. All calculations happen in your browser and nothing is saved or sent to a server.
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Budgeting Calculator, Retirement Calculator, 401(k) Calculator, Social Security Calculator, Life Insurance Calculator and Pension Calculator.
This calculator is for educational purposes only and is not financial advice. Actual terms depend on your lender. Consider speaking with a qualified financial professional before making major decisions.
