Credit Card Payoff

How Credit Card Payoff Time and Payment Are Calculated

A credit card charges interest on whatever balance you’re still carrying, every single month — so a bigger monthly payment doesn’t just reduce your balance faster, it also shrinks how much interest you’re charged along the way. This calculator answers whichever of two questions you’re actually asking about a single card: how long will it take to pay off at the payment you’re making now, or what payment do you need to make to hit a payoff goal by a certain date?

This is deliberately a simpler, single-card tool — if you’re juggling several debts at once and want to compare payoff strategies across all of them, the Debt Payoff Calculator does that instead.

The Formula

Credit card interest compounds monthly on whatever balance remains: each month’s interest charge is $\vA{\text{Balance}} \times \left(\text{APR} \div 12\right)$, added to the balance before that month’s payment is subtracted.

• How long to pay it off: simulated month by month, since there’s no clean formula for “how many months” once the final, smaller cleanup payment is accounted for.
• What payment do I need: solved with the standard fixed-payment loan formula:

$$\text{Payment} = \vA{\text{Balance}} \times \frac{\vB{r}(1+\vB{r})^{\vC{n}}}{(1+\vB{r})^{\vC{n}} - 1}$$

where $\vB{r}$ is the monthly rate (APR ÷ 12) and $\vC{n}$ is your target number of months.

Worked Example

A $5,000 balance at 20% APR:

• Paying $200/month: paid off in 33 months, with $1,522.10 total interest paid (total paid: $6,522.10).
• To pay it off in exactly 24 months instead: you’d need a $254.48/month payment, paying $1,107.50 total interest — less interest than the $200/month plan above, because the balance is cleared faster.

Key Factors to Consider

• A shorter payoff goal requires a proportionally larger payment, not a proportionally shorter wait. Because interest compounds on the remaining balance every month, cutting the payoff time in half doesn’t require exactly double the payment — the actual required payment depends on the interplay between the rate and the target timeline, which is why this calculator’s “solve for payment” mode exists rather than a simple division.
• This is the right tool when you’re focused on a single card, not several debts at once. If you’re managing multiple credit cards or loans and deciding which to prioritize paying down first, the Debt Payoff Calculator’s avalanche/snowball comparison is the more useful tool — this calculator answers the payoff question for one balance in isolation.
• A card’s APR can change over time, especially after a late payment. Some card agreements include a penalty APR that kicks in after a missed or late payment, often substantially higher than the standard rate — check whether your card’s current rate reflects any such penalty before relying on this calculator’s projection.
• Rewards and cashback don’t offset the cost of carrying a balance. Any rewards earned on a purchase are almost always far smaller than the interest that accrues on an unpaid balance at a typical credit card APR — carrying a balance specifically to “earn more rewards” is rarely a good trade financially.

Common Mistakes

• Only ever making the minimum payment. Credit card minimums are often calculated to keep a balance outstanding for a very long time — this calculator’s whole point is showing what a real, specific payment amount actually accomplishes instead.
• Ignoring a promotional 0% APR period’s expiration. A balance transfer or promotional rate that reverts to a much higher standard APR after a set period changes the real payoff math significantly once that period ends — use the promotional rate only for as long as it actually applies.
• Adding new charges while trying to pay off a balance. This calculator assumes no new purchases are added to the balance during payoff — continuing to charge the card works against the payoff timeline shown here.

Useful to Know

A useful gut-check when comparing payoff plans: the total interest paid is roughly proportional to how long the balance stays outstanding, not to the size of the balance alone — which is why shaving even a few months off a payoff timeline, by rounding a monthly payment up to a slightly higher number, can save noticeably more in interest than the size of that rounding might suggest. It’s also worth checking whether a card allows extra payments to be applied directly to principal rather than sitting as a “prepayment” against next month’s minimum — some issuers apply extra amounts differently by default, and confirming this ensures the actual payoff matches what this calculator projects.