💳 Credit Card Calculator
Find out how many months it will take to pay off your credit card balance and how much interest you’ll pay along the way, based on a fixed monthly payment.
How Credit Card Payoff Is Calculated
Credit card balances accrue interest monthly, compounding on whatever you haven’t paid off yet. This calculator uses the standard amortizing-payment formula to figure out how many months of fixed payments it takes to bring the balance to zero.
The monthly interest rate is your APR divided by 12. Each month, interest is added to the remaining balance and your payment reduces it. The number of months (n) needed is found from: n = -log(1 – (r × P) / A) / log(1 + r), where P is the balance, r is the monthly rate, and A is your fixed payment.
- If your payment is less than or equal to the interest charged each month, the balance will never shrink — the calculator flags this case.
- Total interest paid is simply the total of all payments minus the original balance.
Note: This is a simplified educational estimate. Real cards may add fees, have variable rates, or apply minimum-payment rules that change the payoff timeline.