Debt Payoff Calculator
Calculate how long to pay off debt and total interest paid for loans and credit cards.
What Is the Debt Payoff Calculator?
The Debt Payoff Calculator computes how long it takes to pay off a debt with fixed monthly payments, or the monthly payment needed to pay off debt in a target timeframe. Enter the loan balance, interest rate, and either payment amount or desired payoff period to plan your debt elimination strategy.
Formula
How to Use
Enter your current debt balance, the annual interest rate, and either your monthly payment or your target payoff date. The calculator shows months to payoff (or required payment), total interest paid, and an amortization schedule showing balance reduction over time.
Example Calculation
Credit card balance: $5,000, APR: 22%, minimum payment: $100/month. n = −ln(1−5000×0.01833/100)/ln(1.01833) = 101 months (8.4 years). Total interest = 101×100−5000 = $5,100. Increasing to $200/month: 32 months, $1,400 interest.
Understanding Debt Payoff
Debt payoff planning is one of the highest-return financial decisions you can make. Credit card debt at 20% APR costs more than most investments earn. Understanding exactly how long it takes to eliminate debt — and what happens to that timeline with extra payments — provides the motivation and math to accelerate payoff.
The amortization formula reveals a critical insight: doubling your minimum payment dramatically cuts both payoff time and total interest. On a $10,000 debt at 20% APR, paying $200/month takes 94 months and costs $8,800 in interest; paying $400/month takes 32 months and costs $2,800 — a $6,000 saving.
For multiple debts, the debt avalanche strategy (highest rate first) minimizes total interest mathematically. The debt snowball (smallest balance first) is psychologically powerful — the 'wins' of eliminating small debts build momentum. Research suggests the snowball slightly outperforms the avalanche when human psychology and adherence are factored in.
Frequently Asked Questions
Why does it take so long to pay off credit card debt?
High APRs (18–29%) combined with low minimum payments mean most early payments go toward interest rather than principal. Only a tiny fraction reduces the balance, creating a slow-moving payoff timeline.
What is an amortization schedule?
An amortization schedule shows the payment breakdown (principal vs interest) for each month over the life of the loan. Early payments are mostly interest; later payments are mostly principal.
What is the debt avalanche strategy?
The debt avalanche pays minimum payments on all debts except the highest-APR one, which receives maximum payment. This minimizes total interest paid.
What is the debt snowball strategy?
The debt snowball pays minimum payments on all debts except the smallest balance, which receives maximum payment. Psychologically satisfying — early wins motivate continued debt reduction.
Is this calculator free?
Yes, completely free with no registration required.