Credit Card CalculatorFree online financial calculator — instant results, no sign-up
How long to pay off a card at a fixed payment.
Estimates only, based on the inputs and assumptions shown. This is not financial, investment, tax, or legal advice. Prices, rates and local rules may change; crypto scenarios do not predict returns. Confirm important decisions with a qualified professional.
Sign in to save results and favorites.
How the result changes with balance
Each row below was calculated with this tool, keeping every other input at its default and changing only balance from half to one and a half times the default value. Use it to see how sensitive the answer is before you enter your own numbers.
| Balance ($) | Months to pay off | Total interest |
|---|---|---|
| 2,500 | 15 | $365.40 |
| 3,750 | 24 | $887.05 |
| 5,000 (default) | 34 | $1,749.54 |
| 6,250 | 47 | $3,116.01 |
| 7,500 | 65 | $5,304.88 |
About the Credit Card Calculator
This calculator determines how many months it will take to eliminate a credit card balance when making a fixed monthly payment, alongside the total interest paid. It is designed for cardholders aiming to structure a consistent debt payoff plan and see the true cost of their interest charges.
- Balance
- The current outstanding credit card debt, in dollars ($).
- APR
- The annual percentage rate charged on purchases, in percent (%).
- Monthly payment
- The fixed dollar amount you plan to pay each month ($). Must exceed monthly accrued interest.
Formula and method
k = -ln(1 - (B × r) / P) / ln(1 + r) Months = ceil(k) Total Interest = (P × k) - B
- BInitial card balance ($)
- rMonthly interest rate, calculated as (APR / 100) / 12
- PFixed monthly payment amount ($)
- kExact number of repayment periods
- ceil(k)Value of k rounded up to the next whole month
The calculator converts the annual percentage rate (APR) into a monthly decimal interest rate and computes the exact payoff duration using the standard amortization period formula (nper). If the monthly payment is less than or equal to the first month's interest, it returns an error indicating that the payment does not cover interest. The displayed payoff months are rounded up to the nearest integer, while the total interest is computed from the exact payment timeline minus the starting principal.
Worked example
These are the calculator's starting values and the results it actually produces for them.
Inputs
- Balance5000 $
- APR22 %
- Monthly payment200 $
Results
- Months to pay off34
- Total interest$1,749.54
How to use the Credit Card Calculator
- 1Divide the APR by 100 and then by 12 to determine the monthly interest rate.
- 2Verify that the monthly payment exceeds the initial monthly interest charge (Balance × monthly rate).
- 3Calculate the exact payoff duration in months using the logarithmic period equation.
- 4Round the duration up to the nearest integer for full months, and subtract the original balance from total payments to find total interest.
Reading your result
The 'Months to pay off' result shows the total calendar months required to bring the balance to zero assuming no new charges are made. 'Total interest' reveals the cumulative financing cost paid above the original balance over that payoff period.
Limitations
The calculation assumes a constant APR and an unchanging fixed monthly payment with no new purchases or late fees. It does not model variable interest rate adjustments, promotional balance transfer fee windows, or tiered minimum payment rules set by card issuers.
Common questions
Why does the calculator display 'Payment doesn't cover interest'?+
If your fixed monthly payment is equal to or less than the monthly interest generated by your current balance, the balance will never decrease. Increase your monthly payment amount to cover interest and reduce principal.
Does this calculation match my credit card statement's minimum payment warning?+
Not necessarily. Credit card statements usually display payoff estimates based on paying only the minimum payment (which drops as the balance falls), whereas this calculator models a fixed monthly dollar amount until the balance is cleared.
What happens to the final month's payment?+
Because the exact payoff duration rarely lands on a whole integer, the final month's payment is typically smaller than the fixed monthly payment amount.
Does the calculator save my information?+
Calculations run in your browser. While signed in, inputs and results are automatically recorded in account history; saving a result creates a separate saved record.
Further reading
You might also like
Loan Calculator
Payment, total cost and interest on any amortized loan.
Payment Calculator
Monthly payment for a fixed term, or term for a fixed payment.
Currency Calculator
Convert between major currencies (reference rates, update for live rates).
Inflation Calculator
What money is worth after years of inflation.
Sales Tax Calculator
Add or remove sales tax from a price.
Credit Cards Payoff Calculator
Avalanche payoff plan across several cards.
Results are estimates for informational purposes and are not financial, medical or legal advice.