Finance
Credit Card Interest Calculator
Estimate one month's credit card interest from balance and APR.
This result shows roughly how much interest one month adds, and how much a full year would add if the balance stayed the same.
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.
Worked example
For example, a $3,000 balance at 22% APR gives monthly interest of about $55.00 ($3,000 × 22 ÷ 100 ÷ 12), or about $660.00 over a year if the balance is held.
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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