Debt Payoff Calculator
Example: $25,000 in debt at 18% - pay $100 extra/month, save $8,500 in interest
See how extra payments can help you become debt-free faster and reduce the interest paid. Enter your total debt, interest rate, and how much extra you can pay each month. The calculator estimates your payoff date and savings compared with minimum payments only.
Principal paid vs interest paid over time
Total Interest
Interest you will pay
Debt-Free Date
When you will be debt-free
Months to Payoff
Interest Saved
Saved vs minimum payments
Months Saved
Faster than minimum only
Total Paid
How We Calculate This
This calculator uses standard compound interest formulas to simulate debt payoff over time. Monthly interest is calculated on the remaining balance, and payments are applied with interest deducted first, then principal. If the monthly payment does not exceed the first month of interest, the calculator reports that the debt will not amortize with the current payment.
Methodology last reviewed: April 2022. How SparkCalc works
Sources: U.S. CFPB: What is a daily periodic rate on a credit card?
Frequently Asked Questions
What is the debt avalanche method?
The avalanche method prioritizes paying off debts with the highest interest rates first. After making minimum payments on all debts, you put extra money toward the highest-rate debt. This minimizes total interest paid and is mathematically optimal.
What is the debt snowball method?
The snowball method prioritizes paying off the smallest balances first. After making minimum payments, you put extra money toward the smallest debt. While you may pay more interest overall, the quick wins can provide motivation to stay on track.
How much extra should I pay?
Any extra amount helps. Even $50-100 extra per month can save thousands in interest and years of payments. Look at your budget for areas to cut temporarily, or consider ways to increase income specifically for debt payoff.
Should I pay off debt or invest?
Generally, pay off high-interest debt (above 7-8%) before investing beyond an employer 401k match. The guaranteed return of paying off 18% APR debt is hard to beat. For lower-rate debt, you might invest simultaneously.
Will paying off debt improve my credit score?
Yes, reducing your credit utilization (debt relative to credit limits) is one of the fastest ways to improve your credit score. Keeping utilization below 30%, and ideally below 10%, can significantly boost your score.
Related Calculators
You might also find these calculators helpful: Credit Card Payoff Calculator, Loan Comparison Calculator, and Savings Goal Calculator.
Related guides
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This calculator provides estimates for educational purposes only. Actual payoff times may vary based on your specific loan terms, payment timing, and any changes to interest rates or payments.