Credit Card Interest-Per-Day Calculator
Example: Current balance: 7500 $ · Annual interest rate (APR): 22.99 %
| Interest charged per day | $5 |
| Interest charged per month | $144 |
| Annual interest if balance unchanged | $1,724 |
| Interest charged per hour | $0 |
| Daily periodic rate | 0.06% |
Worked example
A $7,500 balance at 22.99% APR has a daily periodic rate of 0.063%. That is $4.72 per day — $197 per month, $1,724 per year — flowing from your account to the card issuer while the balance sits untouched. Every day you delay an extra payment costs nearly $5 in pure interest. Put another way: a $50 restaurant dinner charged to this card and not immediately paid off costs about $61 in total over a year.
Frequently asked questions
How do card issuers calculate daily interest?
The standard method divides your APR by 365 to get the daily periodic rate (DPR), then multiplies by your average daily balance. Each day you carry a balance, that day's interest is calculated and accrues. If you pay in full by the due date, most cards have a grace period and charge no interest at all.
What is a grace period, and does it apply here?
Most credit cards offer a grace period of at least 21 days between the statement closing date and the due date. If you paid your previous balance in full, no interest accrues on new purchases during this window. Interest charges only begin if you carry a balance from month to month. If you already carry a balance, the grace period may not apply to new purchases.
Is the APR the same as the interest rate?
For credit cards, APR and the interest rate are effectively the same — cards charge simple daily interest, not compound interest with separate fees baked in. For other loan types (mortgages, personal loans), APR is broader and includes origination fees, so the APR is higher than the stated rate.
Does this calculation change if I make purchases?
Yes. Your daily interest is based on the average daily balance across the billing cycle. Adding new purchases raises the average; making payments during the cycle lowers it. For simplicity, this tool shows the daily cost at your current static balance — your actual monthly charge varies by purchase and payment timing.