Credit Card Calculator
Find out how long it will take to pay off your credit card balance and how much interest you will pay.
See exactly how many months it will take to pay off a credit card balance under your minimum payment rule, how much interest that costs, and how much time and money an extra monthly payment can save.
How Credit Card Calculator Works
The calculator simulates your balance month by month. Each month it charges interest at APR ÷ 12 on the current balance, then applies a payment — either a percentage of the current balance (with a $25 minimum floor) or a fixed dollar amount, plus any extra payment you enter — and reduces the balance by payment minus interest. This repeats until the balance reaches zero.
Because a percentage-of-balance minimum payment shrinks in dollar terms as your balance falls, the amount actually going toward principal can shrink close to zero, which is why minimum-payment-only payoffs on revolving debt can stretch out for decades even on a modest starting balance.
To show the value of paying more, the calculator runs the same simulation twice — once using only the minimum payment, and once adding your entered extra monthly payment — and compares total months and total interest between the two scenarios.
See It In Action
Who Uses Credit Card Calculator and Why
- Seeing exactly how many months a credit card balance will take to pay off under minimum payments alone.
- Understanding why a percentage-of-balance minimum payment can stretch payoff out for decades on a modest starting balance.
- Testing how much time and interest a fixed extra monthly payment saves compared to paying only the minimum.
- Comparing payoff outcomes across multiple cards to see which benefits most from directing extra payments toward it.
Mistakes to Avoid
- Assuming a percentage-of-balance minimum payment stays a fixed dollar amount — it shrinks every month as the balance falls, so less and less goes toward principal over time, which is exactly why minimum-only payoffs can take decades even on a modest balance.
- Forgetting the calculator assumes no new charges are added to the balance — continuing to use the card for purchases while paying it down will extend the real payoff time well beyond what the tool projects.
- Comparing multiple cards' minimum-payment payoffs without checking which one carries the highest APR — typically the highest-rate card benefits the most in interest saved per extra dollar directed at it.
Tips for Best Results
- If you have balances on multiple cards, run each one through separately with its own balance, APR, and minimum payment rule, then compare which benefits most from extra payments.
- Even a modest extra monthly payment redirects a disproportionate share of your payment away from interest and into principal, given how high credit card APRs typically run — check the specific dollar savings before dismissing a small extra payment as not worth it.
Fixing Common Problems
My payoff timeline looks impossibly long under minimum payments. — This is expected behavior when the minimum is set as a percentage of balance (with a floor like $25) — the dollar amount going to principal shrinks every month as the balance falls, which is the well-documented "minimum payment trap" on revolving debt.
Terms Explained
Minimum payment trap: The effect where a percentage-of-balance minimum payment shrinks in dollar terms as the balance falls, stretching payoff out far longer than expected.
APR (Annual Percentage Rate): The yearly interest rate charged on the card balance, applied monthly at APR ÷ 12 in the payoff simulation.