Credit card payoff & interest calculator
Months to pay off + total interest · runs entirely in your browser
Enter your balance, APR and a fixed monthly payment to see how many months it takes to clear the card and the total interest you will pay. Card interest compounds monthly, so a higher fixed payment cuts both the time and the cost sharply. This is an estimate for general information, not financial advice.
How the calculation works
Each month the calculator adds one month of interest (APR / 12 of the current balance), then subtracts your payment. It repeats until the balance hits zero. If your payment does not even cover the first month's interest, the balance never falls - the tool tells you the minimum payment needed to make progress. The math:
- Monthly interest = balance x (APR / 12)
- New balance = balance + monthly interest - payment
- Total interest = sum of all monthly interest until paid off
Frequently asked questions
How is credit card interest calculated?
Card interest compounds monthly. Each month you are charged your APR divided by 12 on the balance, then your payment is applied. This calculator iterates month by month: it adds that month's interest, subtracts your payment, and repeats until the balance reaches zero - giving the payoff time and total interest.
Why is my minimum payment so slow to pay off the card?
Minimum payments are usually a small percentage of the balance (often 1-3% plus interest). At a 22% APR, most of a minimum payment goes to interest, so the balance barely moves. Paying a fixed, higher amount each month dramatically cuts both the payoff time and the total interest - try it above.
What APR should I use?
Use your card's purchase APR (on your statement or cardholder agreement). If you do not know it, the US average is about 21% (21.52% on accounts charged interest). You can look up your issuer's surveyed range on this site.
Sources
National average APR from the Federal Reserve G.19 Consumer Credit (Q1 2026); issuer APR ranges from the CFPB Terms of Credit Card Plans (TCCP) Survey (CFPB TCCP survey, Jul-Dec 2025). Estimates only - not financial advice. See our disclaimer.
Last updated: 2026-06-29