Enter a card balance and APR to calculate payoff time from a fixed payment, or switch modes to find the payment needed to hit a target payoff date.
How to Use the Credit Card Calculator
Start with the balance and APR, then pick a mode. "Fixed Payment" takes a payment amount and tells you how long payoff takes and what it costs in interest. "Target Payoff Time" flips it — say how many months you want to be debt-free, and it solves for the payment that gets you there.
Fixed Payment → Months: n = −ln(1 − rB ÷ M) ÷ ln(1 + r)
Target Time → Payment: M = rB ÷ [1 − (1 + r)⁻ⁿ]
B is the balance, r the monthly rate (APR ÷ 12 ÷ 100), M the payment, n the number of months. Both directions solve the same underlying relationship — only which variable is fixed and which gets solved for changes.
Card minimum payments are a genuine trap, and it's worth being blunt about why: issuers typically set the minimum around 1–3% of the balance, which on most cards barely clears the interest that accrued that same month. Run a $5,000 balance at 22% APR through "Fixed Payment" at a low minimum and the payoff timeline stretches into years, with early payments going mostly to interest — the balance barely moves for a long stretch before it starts dropping in earnest.
"Target Payoff Time" is the more actionable of the two modes for actually getting out of debt: decide the card should be gone in 24 months, and it tells you exactly what payment that requires, rather than leaving you to guess at a number and check back later.