Credit card interest calculator
Credit card interest calculator: what your APR costs
See what your card's APR costs in a billing cycle and each month, using your balance and payment.
How this works
- Card companies generally divide the APR by 360 or 365 to get a daily periodic rate, depending on the company. You can choose which.
- Each day's interest is the daily rate times that day's balance. A payment lowers the balance from the day it posts.
- By default each day's interest is added to the balance, so interest is charged on interest. You can turn that off.
- It assumes you carry a balance from month to month, so there is no grace period.
- The monthly and yearly figures hold the balance steady and use APR ÷ 12, the same estimate the payoff tools use.
Sources
- CFPB: what is a daily periodic rate on a credit card?
- CFPB: how does my credit card company calculate the interest I owe?
Awaiting expert reviewPreview build. Estimates only; not financial, tax or legal advice.
Common questions
How is credit card interest calculated?
Many card companies calculate interest daily using a daily periodic rate: the APR divided by 360 or 365, depending on the company. Because interest builds daily, paying sooner means less interest when you carry a balance.
What is a daily periodic rate?
The rate charged on your balance each day. It's the APR divided by 360 or 365, depending on the card company.
Why doesn't my statement match exactly?
Card companies use their own balance methods, day counts and posting dates, and new purchases, fees and rate changes all add up. Your statement shows your card's rates and how the balance is figured.
Is the information I enter saved or sent anywhere?
No sign-up is needed. Your numbers are saved only in this browser, and the other tools on the site reuse them.