Debt Payoff Calculator
Find how many months it takes to clear a debt from its balance, APR and payment.
Months to pay off31.6months
Total paid$6,313.60
Total interest$1,313.60
The standard payoff formula is n = −ln(1 − i·B ÷ PMT) ÷ ln(1 + i), where B is the balance, i is the monthly rate (APR ÷ 1200) and PMT is the monthly payment. A $5,000 balance at 18% APR paid at $200/month clears in ≈ 31.6 months, with ≈ $1,314 of interest. If the payment is too small to cover the monthly interest the debt never reduces and the result is undefined (shown as —).
Educational estimate only — not professional financial or medical advice.
Questions
How long will it take to pay off my debt?
It uses n = −ln(1 − i × balance ÷ payment) ÷ ln(1 + i), with i the monthly rate. A $5,000 balance at 18% APR at $200/month takes about 32 months.
Why does it sometimes show no answer?
If your monthly payment is smaller than the interest charged each month, the balance grows instead of shrinking and the debt is never paid off — so the formula has no solution.