Tool · Money
Type in what you owe on the card, its rate and what you'll pay each month, and the calculator shows how many months until it's gone, what the interest adds up to, and what fifty dollars more a month would change.
Where does each number come from?
- Balance
- What you owe today — the current balance in the app or the “new balance” on your last statement. The calculator adds no new purchases to it, so it’s the picture if you stopped using the card.
- APR
- The purchase rate, printed on your statement in the interest-charge section and in your card agreement. The box starts at the average rate people who carry a balance are paying, from the Federal Reserve, which is a fair stand-in until you find yours.
- Monthly payment
- The same amount every month. Your card’s real minimum shrinks as the balance shrinks, so if you type this month’s minimum you’ll get an honest first month and a schedule that only gets better from there. The figure worth a look is how much of that first payment is interest: past half, the balance is barely moving.
What moves the answer?
Let’s say you owe $5,000 at 22% and pay $150 a month. The first month, about $90 of that $150 is interest, and the card is paid off in a little over four years with about $2,800 in interest along the way. Pay $200 a month instead and it’s gone in under three years for about $1,750 in interest — fifty dollars more a month saves about $1,050 and a year and a half. At $250 a month it’s about two years and about $1,300.
The rate matters too, but you can’t change it by typing; the payment is the number that’s yours to move, which is why the calculator shows the fifty-dollar line next to every result.
What does the calculator take as given?
- The rate
- Starts at 22.15%, the Federal Reserve’s average for credit card accounts that were charged interest in the second quarter of 2026, from its consumer credit release of 8 September 2026. That’s the rate people carrying a balance are paying; the average across every card, including the ones paid in full each month, is lower at 20.94%.
- Card rates float
- Most cards charge the prime rate plus a fixed margin, and the prime rate went to 7% on 17 September 2026. When it moves, your rate moves with it, usually within a billing cycle or two. The calculator holds the rate you type flat.
- Why one fixed payment
- Federal rules require your card company to use your own account’s minimum-payment formula, and those formulas differ from card to card, so there’s no honest “typical minimum” to model. A fixed payment you choose is the one number every reader can check.
- How interest is figured
- Monthly, at the yearly rate divided by twelve. Card companies figure it on your average daily balance, which lands close to this but not on it.
- What's left out
- Annual fees and late fees. Promotional 0% periods and balance transfers. New purchases. Each one changes the math, and each one is in your card agreement.
Five thousand dollars at twenty-two percent is a made-up card to show the shape of the payoff; your statement carries your balance, your rate and this month's minimum, and those three are all the calculator needs.
Sources
- Federal Reserve, Statistical Release G.19, Consumer Credit, Terms of Credit table — release of 8 September 2026: credit card plans, accounts assessed interest 22.15%, all accounts 20.94%, second quarter 2026.
- Federal Reserve, Statistical Release H.15 — bank prime loan rate 7.00% on 18 September 2026, release of 21 September 2026.
- Consumer Financial Protection Bureau, Regulation Z, Appendix M1 to Part 1026 — Repayment Disclosures, (b)(1): issuers must use the minimum-payment formula that applies to the cardholder’s account.
- Bills & Beans, The Money Numbers That Change Every January — the G.19 and H.15 figures with their quotes and dates.