TidyToolsHow credit card payoff works
Credit card interest is charged on your balance every month, so part of each payment just covers that month's interest and only the rest reduces what you owe. Because the balance shrinks slowly at first, a fixed payment clears the card faster the higher it is — and if the payment barely beats the monthly interest, the balance can take years to move. This calculator steps through your balance month by month, applying interest and then your payment, until it reaches zero.
The key figure to watch is the total interest. On a high-APR card, paying only a little above the minimum can mean paying back far more than you borrowed. Nudging the monthly payment up — even by a small amount — usually cuts both the time and the interest dramatically.
A worked example
Owe $4,000 at 19.9% APR and pay $150 a month. The card charges about $66 of interest in the first month, so only ~$84 of your first payment reduces the balance. Kept up, it takes about 36 months to clear and costs roughly $1,325 in interest. Raise the payment to $250 a month and you'd be done in about 19 months with roughly $690 of interest — less time and far less interest.
Warning: when the payment is too low
If your monthly payment is less than the interest charged that month, the balance grows instead of shrinking and the card is never paid off. If you see that warning, you'll need a higher payment, a lower rate (for example a balance transfer), or both.
Frequently asked questions
Does this assume I stop spending on the card?
Yes. It calculates payoff for the balance you enter with no new purchases added. If you keep spending, it will take longer.
Why does a small payment increase cut interest so much?
Extra payment goes straight to the principal, which shrinks the balance interest is charged on. That compounds every month, so a modest increase saves a disproportionate amount.
What is a balance transfer?
Moving your balance to a card with a lower (often 0%) introductory rate. Less interest means more of each payment clears the debt — but check the transfer fee and when the promo rate ends.
Is this financial advice?
No. It's a free math tool for estimates only, not financial advice. Your card's exact interest method may differ slightly.