Credit-Card Interest Cost Calculator
Interest is a purchase with no object attached. Converting the monthly charge into annual work hours shows how much earning time goes only to carrying yesterday’s balance.
$185 of interest each month becomes $2,220 per year. At $20 of take-home pay per hour, that is 111 work hours—nearly fourteen 8-hour workdays.
Use the interest actually charged
Find the interest-charge line on recent statements. If it varies, average the last three months rather than estimating from the minimum payment.
Separate interest from principal
Only the part that reduces principal lowers what you owe. Track interest separately so the carrying cost does not disappear inside the payment.
Compare one extra payment
Use the result to price the tradeoff of sending extra money to the balance. Exact payoff savings depend on the APR, balance, timing, and future charges.
Run your own numbers
The free calculator works in your browser and requires no bank connection or account.
Open the calculator with this example →