Given a balance, APR, and a monthly payment, calculate how long it will take to pay off and how much interest you will pay.
Balance, rate, and what you can pay each month.
| Pay instead | Debt-free in | Time saved | Interest saved |
|---|---|---|---|
| $250(+$50) | 2 yr 3 mo | 9 mo | $601 |
| $300(+$100) | 1 yr 9 mo | 1 yr 3 mo | $930 |
| $450(+$250) | 1 yr 1 mo | 1 yr 11 mo | $1,389 |
The math assumes a fixed APR and a fixed payment. Variable APRs move with the prime rate, and minimum-payment schedules that shrink with the balance stretch payoff far longer than a fixed payment does. A 0% balance transfer can pause the interest clock while you pay principal.
The simulation runs your balance forward one month at a time. Each month, interest accrues at one twelfth of your APR, your payment lands, and whatever clears the interest reduces principal. Early on, a painful share of every payment is interest. As the balance shrinks, the same payment retires more principal and the process accelerates. That curve is why the last $1,000 disappears so much faster than the first.
If your payment does not even cover the monthly interest, the balance grows forever and the calculator says so plainly. The escape velocity at 25% APR on $5,000 is about $105 a month, and that only holds the line. Real progress starts meaningfully above it.
Issuer minimums are typically 1% to 2% of the balance plus interest, recalculated monthly. Because the payment shrinks as the balance shrinks, the principal reduction stays tiny the whole way down. A $5,000 balance at 24.99% APR on minimum payments takes well over 20 years and more than doubles what you repay.
A fixed payment breaks that trap. Pick a number, hold it as the balance falls, and the shrinking interest works for you instead of the issuer. The accelerator table above shows exactly what each extra $50 buys in months and dollars. It is consistently more than people expect.
Written by the CreditCardSignups editorial team. Card rates and offers verified June 10, 2026. Point valuations updated 2026-06-10. Card terms change often, so confirm details on the issuer's site before applying.
