Adding new charges
New spending can erase progress even when monthly payments are consistent.
Debt calculator
Debt Payoff Calculator
Estimate how long it may take to pay off a balance and how much interest could be paid with a fixed monthly payment and optional extra payment.
Updated: June 10, 2026
Calculate payoff estimate
Payoff time—
Total interest—
Total paid—
Live scenario comparison
Current payment—
+$50 monthly—
+$100 monthly—
Payoff cost breakdown insight
This insight updates to compare original balance with estimated interest.
Starting balance—
Total interest—
Debt payoff formula approach
Instead of using one closed formula, this calculator simulates month by month:
- Add monthly interest to the balance.
- Subtract the monthly payment and extra payment.
- Repeat until the balance is paid off.
Worked example
For an $8,000 balance at 18% interest with a $300 regular payment plus $100 extra, the payoff time is much shorter than paying the minimum alone. Extra payments can reduce both time and total interest.
Common mistakes
Ignoring interest rate differences
Higher-rate debt usually grows faster and can be more expensive to carry.
Choosing a payment that is too low
If the payment barely covers interest, payoff may take a very long time.
How to read the payoff estimate
The payoff time shows the number of months needed under the exact payment entered. The total interest line is the estimated cost of carrying the balance during that payoff period. If the result says the payment is too low, the entered payment does not reduce principal under the simplified monthly-interest model.
Related tools and guides
For credit-card-specific minimum-payment behavior, try the credit card minimum payment calculator. To compare debt strategies, read debt snowball vs avalanche, estimate budget pressure with the debt-to-income calculator, or summarize several APRs with the weighted average interest rate calculator.
FAQ
Does this support multiple debts?
This first version estimates one balance. A future version can compare snowball and avalanche methods across multiple debts.
Does the result include fees?
No. Late fees, transfer fees, and account-specific charges are not included.
What if the result says payment is too low?
That means the monthly payment may not reduce the balance under the assumptions entered.
How to read this estimate
The result is an educational estimate based only on the inputs shown on this page. It is useful for comparing assumptions, spotting cost drivers, and understanding the formula, but it is not a recommendation or a guarantee.
Before using a result for a real decision, compare it with official documents, local rules, fees, taxes, insurance, and any professional guidance that applies. See How We Calculate and the Disclaimer for more context.
Method and verification trail
- Method used: The calculator simulates balance decline month by month using the entered APR, regular payment, and extra payment until the balance reaches zero.
- Primary source type to verify: Card statements, loan statements, payoff quotes, APR disclosures, and account terms that describe minimum-payment and posting rules.
- What to confirm in real documents: Actual APR, whether new charges are excluded, fees, penalty APRs, promotional-rate expirations, and whether the lender recalculates minimums or applies payments differently.
- Scope limit: This page does not model issuer-specific daily interest, multi-balance allocation quirks, settlement offers, or account servicing edge cases.
For site-wide methodology, review How We Calculate. For sourcing and corrections standards, review Editorial Policy.
Scenario comparison
For debt payoff, compare the current payment, a small extra-payment case, and a more aggressive payoff case. The current payment shows the path if nothing changes. A small extra amount can show whether even a modest change shortens the timeline. The aggressive case helps you test a temporary sprint, but it should still leave room for essentials and irregular bills.
If you have more than one debt, run this calculator for the highest-rate balance and the smallest balance separately. That makes the trade-off between avalanche and snowball approaches easier to understand without turning the estimate into advice.
Current payment
Use the payment you already make to see the baseline payoff time and interest cost.
Small extra
Add an amount that can survive normal months, not just a perfect month.
Focused sprint
Test a temporary larger payment and compare time saved with the pressure it creates elsewhere.
Result quality checklist
- The payment is higher than monthly interest so the balance can actually decline.
- No new charges are assumed during the payoff period.
- Fees, promotional-rate expirations, and minimum-payment rules are reviewed separately.
- The payoff plan still leaves room for essentials, emergencies, and required minimums on other debts.
Before you rely on the number
Use the calculator as a comparison tool rather than a final answer. The most helpful result is usually the direction of change: which input moves the outcome most, which assumption creates the biggest risk, and whether the monthly cash flow still feels realistic after normal life expenses. Save or write down the inputs used for each scenario so you can compare them consistently later.
Any simplified calculator leaves out details that can matter in real accounts, contracts, tax rules, and local markets. If a result will influence a major purchase, loan, payoff plan, savings target, or household budget, compare it with official documents and independent estimates. Treat surprising results as a prompt to check the inputs first, then review the assumptions behind the formula.
Related calculators
Use the debt avalanche calculator for a highest-APR multi-debt order, the credit card payoff calculator for card-specific planning, the debt-to-income calculator for monthly obligation pressure, and debt snowball vs avalanche to compare common payoff frameworks.