Debt Payoff Calculator

Enter the balance, APR, and monthly payment. Add an extra payment if you will pay more. See the months to pay off, total interest, and total paid.

Smart Tips

• The extra payment is added to the monthly payment before anything else is calculated.

• One month of interest is the balance times the APR divided by 12.

• If the combined payment does not cover that interest, the balance will not be paid off, and no month count is shown.

• The last month is smaller when the remaining balance plus that month of interest is less than a full payment.

• At a 0% APR, total interest is $0.00 and total paid equals the balance.

The Formula

Interest for one month = balance × (APR ÷ 12)
Months from log(payment / (payment − r × balance)) / log(1+r)

r = Monthly rate
APR ÷ 12, with APR entered as a percent and then divided by 100

payment = Combined payment
Monthly payment plus any extra payment

months = Payments until zero
Rounded up to a whole month. At 0% APR, balance ÷ payment, rounded up

paid = Total paid
Sum of the payments, with a smaller final payment when one is enough

If the payment does not cover a month of interest, the balance will not be paid off and no month count is shown. Total interest is total paid minus the starting balance.

Key Insights

Interest First

Each month the balance is charged interest before the payment reduces it. A payment that only matches the interest never reduces the balance.

Extra Payment

An extra amount is added to the monthly payment. It is not a separate one-time payment.

Last Month

The final payment is only the remaining balance plus that month of interest when that is less than a full payment.

Zero APR

With no interest, the months are the balance divided by the payment, rounded up, and total paid equals the balance.

Frequently Asked Questions

The payment used is the monthly payment plus any extra payment. Leave the extra payment blank and it counts as zero. One month of interest is the balance times the monthly rate. The monthly rate is the APR divided by 12.

The balance will not be paid off. No month count, total interest, or total paid is shown.

When the payment is greater than one month of interest, the months to payoff are the smallest whole number of payments that brings the balance to zero. At an APR above 0% that count is log(payment / (payment − r × balance)) / log(1+r), rounded up to a whole month. r is the APR divided by 12. At a 0% APR, the months are the balance divided by the payment, rounded up to a whole month.

The last month is the remaining balance plus that month of interest when it is smaller than a full payment. Total paid is the sum of the payments, including that smaller last payment. Total interest is total paid minus the starting balance. At a 0% APR, total paid equals the balance and total interest is $0.00.

The formulas in the formula section on this page are the ones this calculator runs. No outside rate table is used unless the page says otherwise. Source: CFPB paying down debt: https://www.consumerfinance.gov/ask-cfpb/how-can-i-pay-down-my-debt-en-1443/.

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Months to Payoff

Enter values to calculate

Total Interest

Total Paid

Note:One month of interest is the balance times the APR divided by 12. If the payment does not cover that interest, the balance will not be paid off. These figures are estimates, not a credit offer.