Credit Card Payoff Calculator
Free credit card payoff calculator. Model snowball or avalanche payoff for multiple cards and see your debt-free date and total interest. No signup.
A credit card payoff calculator simulates month by month how one or more card balances are cleared by a fixed total monthly payment, and reports the debt-free date, months to payoff, total interest, and total paid. With the defaults — $3,500 at 22.99% and $1,200 at 18%, paying $400 a month — it clears both cards in 15 months and costs $675 in interest on the snowball setting.
How the simulation works
- List each card on its own line as
balance,APR, for example3500,22.99. - Enter one total monthly payment across all cards.
- Choose snowball (target the smallest balance) or avalanche (target the highest APR).
- Each month interest is accrued at APR ÷ 12 on every open balance, then the remaining payment is allocated: every card receives a minimum of 2% of its balance or $25, whichever is larger, and whatever is left attacks the target card.
The loop stops when balances reach zero or when the payment no longer covers the month’s interest. If that second condition hits, the plan never pays off and no payoff month is reached.
Worked example — the defaults
Monthly rates: 22.99% ÷ 12 = 1.9158% on card A, and 18% ÷ 12 = 1.5% on card B. In month one:
| Item | Amount |
|---|---|
| Interest on card A ($3,500 × 0.019158) | $67.05 |
| Interest on card B ($1,200 × 0.015) | $18.00 |
| Total interest this month | $85.05 |
| Left for principal ($400 − $85.05) | $314.95 |
| Minimum to A (2% of $3,500 = $70, above the $25 floor) | $70.00 |
| Minimum to B (2% of $1,200 = $24, raised to the $25 floor) | $25.00 |
| Extra to the snowball target, card B | $219.95 |
| End-of-month balances | A $3,430 / B $955.05 |
Snowball targets the smaller $1,200 balance first, so card B absorbs the leftover. Repeat that 14 more times and both cards are clear.
Snowball vs avalanche on the same debt
| Strategy | Months | Total interest | Total paid |
|---|---|---|---|
| Snowball (smallest first) | 15 | $675 | $5,375 |
| Avalanche (highest APR first) | 15 | $614 | $5,314 |
The avalanche wins by $61 here because it targets the 22.99% balance. The payoff month is identical because a $400 payment is large enough to clear both cards at roughly the same time — on larger balances or a tighter budget the gap widens.
What a bigger payment is worth
Same two cards, snowball setting, different total payments:
| Monthly payment | Months | Total interest |
|---|---|---|
| $200 | 33 | $1,534 |
| $300 | 21 | $936 |
| $400 | 15 | $675 |
| $600 | 10 | $451 |
| $800 | 8 | $337 |
Common mistakes
- Paying only the minimum. The minimum is usually a percentage of the balance, so it shrinks as you pay down; the balance can take decades to clear.
- Treating APR as a monthly rate. Divide by 12 before comparing to a monthly figure.
- Running up new charges. New spending accrues interest immediately and resets the clock.
- Assuming the two strategies always differ. When the payment is large relative to the balances, snowball and avalanche can tie.
Why did snowball and avalanche give the same month count?
Because the fixed payment was big enough that both cards were cleared almost simultaneously. The strategies only diverge meaningfully when the payment is small relative to total debt or one card’s rate is much higher.
What minimum payment does the simulation assume?
2% of each card’s balance, with a floor of $25. That mirrors common issuer formulas, but check your actual statement — some issuers use 1% plus interest, which changes the schedule.
What if my payment does not cover the interest?
The simulation stops without a payoff date. Raise the monthly payment or negotiate a lower rate; otherwise the principal cannot fall.
Is a balance transfer worth it?
A 0% promotional card can stop interest for 12 to 21 months, but transfers usually cost 3–5% of the balance and the rate resets afterwards. On $4,700 of debt, a 3% fee is $141. Compare that with the $614 to $675 of interest the simulation charges over 15 months at these rates — a transfer can win if you clear the balance before the promotion ends, and lose if you do not.
Card payoff is the same amortization math as any installment loan, so the auto loan calculator is a useful comparison if you are juggling both. To see what retiring the same money would grow into instead, run the retirement calculator.