Credit Card Interest Calculator

See what your credit card is costing you. Enter your balance, APR and monthly payment for a month-by-month breakdown.

How is interest calculated?
Credit card daily accrual — used by all major UK credit cards. Interest accrues every day at APR ÷ 365. Enter your balance and monthly payment to see exactly what your card is costing you.
Your details
£
% APR
months
Promotional period (optional)
Include interest-free months? e.g. 0% credit card promotional period
months
Please check your inputs. Free months must be less than the total term.
Total Interest Payable
—
Monthly Payment
—
per month
Total Repayable
—
principal + interest
Month-by-month
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Results are a guide only. Always check your statement and lender for your actual interest rate, fees, and minimum payment.

  • It excludes any default charges or annual card fees
  • It assumes no further debt is added to the card
  • It assumes the interest rate stays the same
  • Some card providers may have different minimum repayments — check your statement if unsure