Credit Card Interest Calculator
See exactly how much interest your credit card balance accrues each month.
Enter your numbers and select Calculate to see results.
About This Calculator
Credit card interest is typically calculated daily using your APR. This calculator shows your daily periodic rate and estimates the interest that will accrue on your current balance over the next billing cycle, so you can see the direct cost of carrying a balance.
How This Is Calculated
Daily Interest = Balance × (APR ÷ 365)
A $3,000 balance at 24% APR accrues about $1.97/day, or roughly $59.18 over a 30-day billing cycle.
Assumptions
- Uses a 365-day daily periodic rate, the most common method issuers use.
- Assumes the balance is constant through the cycle, ignoring new purchases or payments.
Frequently Asked Questions
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Last updated January 15, 2026. Results are estimates for informational purposes only — read our disclaimer.