Minimum Payment Calculator: The True Cost of Paying the Minimum

Minimum payments are designed to be affordable, not to retire a balance. They are typically calculated as the greater of a small percentage of the balance (often 1–3%) or a flat dollar floor (often $25–$35). On a high-APR balance, the early minimum payment can barely beat the monthly interest, which is why a credit-card balance can survive for a decade even when payments never miss.

This calculator simulates payoff month by month under two scenarios — minimum only, and minimum plus an extra payment you choose with a slider — and reports payoff time, total interest paid, the interest-to-principal ratio, and how much you save by adding the extra payment. Move the slider; the numbers update instantly.

A 24.99% APR is about 2.08% per month. On a $5,000 balance, the first month’s interest is roughly $104. If the minimum payment is 2% of the balance ($100) or a $25 floor — whichever is larger — then the borrower pays $100, of which $104 was interest. Principal actually grew that month. The next month, the borrower pays 2% of a slightly larger balance and so on, in a slow grind that can run more than 25 years on a $5,000 starting balance.

The CARD Act of 2009 required issuers to include a Minimum Payment Warning Box on every statement, showing the years and total interest implied by paying only the minimum. Look for it on your statement — the numbers tend to be eye-opening.

Percentage of balance: typically 1–3% of the statement balance. Common for general-purpose credit cards.

Percentage plus interest: 1% of balance plus any interest and fees from the current cycle. This is the Regulation Z “safe harbor” formula and is required for some subprime cards. It pays interest faster than a flat percentage formula but leaves principal moving slowly.

Flat dollar floor: a minimum dollar amount (e.g., $25, $35, or $40) regardless of balance, as long as the balance is above that floor. When a flat floor kicks in on a small balance, the implied payoff timeline shortens dramatically.

The calculator lets you set both the percentage and the floor so you can model your specific cardholder agreement.

Adding $50 or $100 a month to the minimum is rarely transformative for a single month’s cash flow, but the compound effect over many months is large. Every extra dollar paid early reduces the principal that all future months’ interest accrues on. The calculator shows this directly: with a $5,000 balance at 24.99% APR, moving from minimum-only to a minimum plus $50 typically cuts payoff time roughly in half and saves several thousand dollars in interest.

The slider lets you find the lowest extra-payment amount that still produces a tolerable payoff timeline. For most borrowers, the right answer is whatever amount keeps the monthly budget sustainable but pays the balance off in under 24 months.

It does not model: new purchases during payoff (which reset the grace period and add to the balance immediately), promotional APRs that revert, late fees, penalty APRs triggered by a missed payment, deferred-interest store-card structures (where if you don’t pay the full balance by the promo end date, all accrued interest is charged retroactively), balance-transfer fees, or hardship-plan repricing.

Each of those can move the actual cost significantly. Treat the result as a planning floor: your real-world cost is at least this much and probably more if any of the above apply.