KitRoost

Debt Payoff Calculator

One balance, one APR, one monthly payment. Get the exact payoff month, total interest, and what each extra $50 does. Works for cards, store cards, payday alternatives, medical bills, student loans.

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Payoff time—
Total interest—
Total paid—
Debt-free month—
With +$50/mo—
With +$100/mo—
With +$200/mo—
Minimum-payment trap*—

*Minimum payment modeled as 1% of balance + interest + $5 with a $25 floor — the standard card formula. On most balances it stretches the payoff into years and thousands in extra interest.

How the math works

Month loop: interest = balance × APR ÷ 12, principal = payment − interest, balance drops by that principal. Repeat until zero. No rounded averages, real amortization.

Payment floor: if your payment is below the first month's interest, the balance grows forever; the tool says so instead of pretending.

Extra tiers: same loop at +$50, +$100, +$200, reporting months and interest saved versus your plan.

Minimum trap: 1% of balance + interest + $5, floor $25, capped at the payoff amount. Classic long-tail schedule.

Disclaimer. Fixed APR, monthly compounding, no fees, no rate changes, no additional charges. Card APRs compound daily; the monthly model lands within a few percent of statement reality.

Frequently asked questions

How long to pay off $5,000 at 25% APR paying $150 a month?

About 58 months, and roughly $3,600 in interest along the way. The same balance at $200 a month is cleared in about 36 months with around $2,100 of interest. That $50 a month is the difference between five years of interest and three.

What is the minimum payment trap on credit cards?

Minimums are usually 1% of the balance plus interest. That schedule stretches a $5,000 balance into 15+ years of payments and thousands in interest. A fixed payment you can sustain beats the minimum every time.

Is it better to pay one card faster or spread payments?

Pure math: put every extra dollar on the highest APR first (avalanche) and you pay the least interest. The psychological win of killing a small balance (snowball) is worth paying a little more interest for if it keeps you paying.