How to Use This Calculator

Enter your current balance, your card's APR (found on your statement or cardholder agreement), and the fixed monthly payment you plan to make. The calculator shows how many months it will take to reach a zero balance and how much of that total is interest.

It also runs a side-by-side comparison against a fixed-rate consolidation loan at a reference rate, so you can see roughly how much interest a lower, fixed rate could save versus continuing to pay down the card at its current APR.

What the Inputs Mean

  • Balance: Your current outstanding balance on the card.
  • APR: Your card's annual percentage rate on purchases or balances, found on your most recent statement.
  • Monthly Payment: The fixed amount you plan to pay each month — must be more than the interest accruing that month, or the balance will never shrink.

Assumptions & Formula

  • This calculator assumes you make no new purchases on the card and pay the exact same fixed amount every month until the balance reaches zero — real cards with variable minimum-payment formulas or added purchases will differ.
  • The consolidation comparison assumes a fixed 12.99% loan at the same monthly payment over the same calculation method, purely to illustrate the effect of a lower, fixed rate. It is not a quoted or guaranteed rate, and actual consolidation loan APRs vary significantly by credit profile.
  • If your payment doesn't exceed the interest accruing on your balance, the calculator will tell you directly rather than showing a misleading payoff date — this is a real mathematical limit, not a bug.

Formula: Months to payoff = −ln(1 − (r × B) ÷ M) ÷ ln(1 + r), where B is the balance, M is the fixed monthly payment, and r is the monthly rate (APR ÷ 12 ÷ 100). This is the standard formula for paying off a revolving balance with a fixed payment, solved for time rather than payment amount.

Worked Example

Take an $8,000 balance at 22.99% APR with a $250 fixed monthly payment. The monthly rate is about 1.916%. Solving the payoff formula gives roughly 43 months to a zero balance, with total interest of about $2,750. Run the same $8,000 balance and $250 payment through the consolidation comparison at a fixed 12.99% instead, and the payoff time drops to about 36 months with roughly $1,000 in interest — illustrating why a lower, fixed rate can meaningfully shorten both the timeline and the total cost even at the same monthly payment.

Frequently Asked Questions

Why does the calculator say my balance will never be paid off?

If your monthly payment is less than or equal to the interest accruing that month, the balance mathematically cannot shrink — you'd be paying interest only, forever. Increase your monthly payment until the calculator shows a payoff time.

Is the 12.99% consolidation rate a real offer?

No — it's a fixed reference rate used only to illustrate how a lower, fixed-rate loan compares to continuing to pay down a card at a typical card APR. Actual consolidation loan rates depend on your credit profile and the lender.

Does paying more than the minimum always save money?

Yes. Any amount above your card issuer's minimum payment reduces the balance faster and reduces the total interest you'll pay, since interest is calculated on the remaining balance each month.

What if I have multiple credit cards?

Run each card through the calculator separately using its own balance, APR, and payment, or total them together as a rough estimate if you plan to pay them down in parallel at a combined fixed payment.

Sources

  • Methodology note — The 12.99% consolidation reference rate is illustrative and not pulled from a live data feed. Your card's own APR is the number that should come directly from your statement.