The minimum payment trap
Credit card statements list a minimum payment due, and it's tempting to treat that number as the "normal" amount to pay. In reality, minimum payments are set deliberately low — often just 1–3% of your balance, or a small flat floor amount, whichever is higher. Paying only that amount is, mathematically, the slowest and most expensive way to clear a balance.
The reason is that the minimum payment recalculates every month based on your remaining balance. As your balance slowly drops, your required minimum drops too — which means the portion of your payment going toward the principal shrinks along with it. Early on, a large share of every minimum payment is pure interest.
How this calculator works
Each month, we compute your minimum payment as the greater of a percentage of your current balance (you can adjust this, commonly 1–3%) or a fixed floor amount (commonly $25–$35). We then apply that payment — first to interest, then to principal — and repeat until the balance reaches zero, tracking the total time and total interest along the way.
One important edge case: if the percentage you enter is at or below your monthly interest rate (your APR divided by 12), the minimum payment never catches up to the interest, the balance never falls, and the calculator will report that the card is never paid off. A $5,000 balance at 24.99% APR with a flat 2% minimum is exactly this situation.
A worked example
Take a $5,000 balance at 24.99% APR. That APR is about 2.08% in interest per month — roughly $104 on the first statement. If your minimum payment is 2% of the balance (about $100 to start), it doesn't even cover that month's interest, so the balance never goes down and the card is never paid off — no matter how long you keep paying. A flat percentage minimum that's lower than your monthly interest rate is a debt that grows forever.
Nudge that minimum up to 3% of the balance and the card does finally amortize — but it takes about 21 years and roughly $10,000 in interest, more than double the original balance. Even at a 4% minimum it's still around 12 years and $5,000 in interest.
Compare that to a fixed $200/month payment on the same balance: the debt is gone in 3 years for about $2,135 in interest. The single biggest improvement you can make is to stop paying a shrinking percentage and commit to a fixed amount instead.
How to escape the minimum payment cycle
- Switch to a fixed payment amount instead of the shrinking minimum, and set it comfortably above your first month's minimum so it always covers the interest with room to spare. Holding that number steady is what actually retires the balance.
- Use the Extra Payment Calculator to see exactly how much time and interest a specific extra amount would save you.
- If you're juggling several cards on minimum payments, the debt avalanche method helps you prioritize which one to attack first.
- Consider whether a balance transfer to a lower APR would meaningfully reduce how much of each payment goes to interest.