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Credit Card Interest Calculator

Estimate one month's credit card interest from balance and APR.

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Formula

Monthly interest equals balance times APR divided by 100, divided by 12.

How it works

Real card interest uses average daily balance and may vary by transaction type, so this is a simplified estimate. Cash advances often carry higher rates and immediate interest.

FAQs

Why divide by 12?
APR is annual, so one month is roughly one twelfth.

What is average daily balance?
The average of each day's balance in the billing cycle — the usual basis for card interest.

How do I avoid it?
Pay the full statement balance by the due date.

Are these figures financial advice?
No — they are estimates for planning only, not financial advice. Check with a qualified adviser for decisions involving large sums.

Estimates only, not financial advice. Figures are approximate and do not include all fees, taxes, or changing rates unless stated.

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