Credit Card Calculator – See the True Cost of Credit Card Interest

The credit card calculator reveals the true cost of revolving debt. When you pay only the minimum, interest works against you — you pay interest on interest, known as negative compounding. A $5,000 debt at 20% APR can cost you over $10,000 if you only make minimum payments.

The critical factor is the ratio between your monthly payment and new purchases. If you keep spending on your credit card while trying to pay off debt, the balance may never reach zero. This calculator simulates exactly that scenario and shows you when — or if — your debt will be paid off.

The most effective payoff strategy is the ‘Avalanche’ method — paying off the card with the highest interest rate first while maintaining minimum payments on the rest. A popular alternative is the ‘Snowball’ method — starting with the smallest balance for motivation. Either way, the key is to stop adding new debt.

How to Use the Credit Card Calculator

Enter your current balance, the monthly payment you’re willing to make, the annual interest rate (APR), and new monthly purchases — and the calculator will show you exactly how many months it takes and how much interest you’ll pay.