Credit Card Interest Calculator

Estimate how expensive a credit card balance may become by modeling monthly interest, payoff time, and total paid at your planned payment level.

Credit card balance

APR

Monthly payment

First month interest

$162.21

Payoff time

4 years, 8 months

Total interest

$5,340.48

Total paid

$13,840.48

Interest check

This calculator assumes no new charges and a stable APR while you pay the balance down. If the monthly payment is below the monthly interest charge, the balance will not amortize and the payoff timeline will not converge.

How to Use

Enter the current credit card balance and the APR being charged on that balance.
Add the monthly payment you plan to make while avoiding new purchases on the card.
Review the first month of interest to see how much of the payment goes to financing cost right away.
Compare the payoff time and total interest so you can judge whether a higher payment or transfer strategy is worth it.

Frequently Asked Questions

What does this calculator show that the minimum payment does not?

It shows how long the balance may last and how much interest could build up, which is often not obvious when you only look at the minimum amount due.

Does this assume I stop using the card?

Yes. The estimate assumes no new charges and a steady APR while you pay the balance down.

Why is the first month of interest useful?

It gives you a fast reality check on how much of your payment is being absorbed by interest before the balance meaningfully starts to fall.

What if my payment is too low?

If the payment does not cover monthly interest, the balance will not amortize. The calculator warns you when that happens.

Should I focus on interest cost or credit utilization first?

Often both matter. High-card APRs make interest cost urgent, while high utilization can also hurt credit health, so many people compare this page with a utilization calculator.