Debt Payoff Calculator

About this calculator

This calculator works backward from an amortization schedule: given a starting balance, a fixed monthly payment, and an annual percentage rate (APR), it computes how many months it takes to bring the balance to zero, applying interest each month before the payment reduces principal. It also totals the interest paid over the payoff period, showing how much of each payment goes to interest versus principal.

This is the exact math behind credit card minimum-payment traps and personal loan payoff plans — a card charging 22% APR with only minimum payments can take years longer and cost far more in interest than a fixed, higher payment would.

People building a debt-free plan for credit cards, personal loans, or store cards use this to compare payment strategies, financial counselors illustrating the cost of minimum payments to clients, and anyone deciding whether to throw extra money at a balance all rely on this calculation to see the real payoff timeline.