Finance & Money
Debt Payoff Calculator
Use this debt payoff calculator for personal loans, cards, or any amortizing balance with a fixed payment.
Months to payoff
—
- Total interest
- —
- Payoff years
- —
Student quick launch
Grade planning, algebra checks, and formulas students reach for most.
Study path
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Follow these when you want the formula behind the answer, a short lesson, or nearby tools in the same topic.
What this debt payoff calculator solves
It answers one question for any amortizing debt — a personal loan, a card balance, a medical bill on a payment plan: with this balance, this APR, and this fixed monthly payment, how many months until zero, and how much interest accrues along the way?
Payoff-time formula
B is the balance, PMT is the fixed monthly payment, and i is the monthly rate. Each month, interest (balance x i) is charged first and the remainder of the payment reduces the balance. As the balance falls, less of each payment goes to interest, so payoff accelerates near the end.
| Monthly payment | Est. payoff time | Est. total interest |
|---|---|---|
| $250 | ~66 months (5.5 years) | ~$4,500 |
| $450 | ~32 months (2.7 years) | ~$2,400 |
| $700 | ~19 months (1.6 years) | ~$1,300 |
The table is a worked illustration for a $12,000 balance at 12% APR. Notice the pattern: raising the payment shortens the timeline faster than proportionally, because less time paying means less time accruing interest.
- New borrowing is not modeled — the estimate assumes the balance only goes down.
- Variable APRs can change the timeline; the math holds the rate fixed.
- Fees and penalties add to the balance and are not included.
- The final month's payment is usually partial, so real totals run slightly below the estimate.
Use the output to compare scenarios — what an extra $100 per month does to the timeline, or how a lower APR changes total interest — rather than as a guaranteed payoff date.
How to use it
- Enter total balance.
- Enter APR.
- Enter monthly payment.
How to read the answer
The payoff time is an estimate assuming the payment and APR stay fixed.
Common mistakes and edge cases
- New debt is not included.
- Variable rates can change payoff time.
- Fees can increase the balance.
Worked examples
Personal loan payoff
Months to payoff
32 months
Aggressive payoff
Months to payoff
11 months
Frequently asked questions
How can I pay debt faster?+
Increase the monthly payment, reduce APR, or avoid new balances.
Does this work for multiple debts?+
Use a weighted or average APR for a rough total, or the snowball calculator for separate balances.
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Last updated: May 8, 2026