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Enter your balance and APR to see exactly how much interest you're paying every day, every month, and every year.
Credit card interest doesn't wait until the end of the month. Most issuers calculate interest daily using your Daily Periodic Rate (DPR) — your APR divided by 365. Every day you carry a balance, a small percentage of that balance is added to what you owe. At 22% APR, a $5,000 balance accrues about $3.01 per day. That might seem small, but over a year it adds up to over $1,100 in interest alone — on a balance that isn't even growing from new spending.
Your actual monthly interest charge is based on your Average Daily Balance (ADB), not your end-of-month balance. If you carried $5,000 for 15 days and then made a $1,000 payment, your ADB for that 30-day cycle is about $4,500. The interest charge would be: $4,500 × (22.99% ÷ 365) × 30 = $85.15. This is why making payments earlier in the billing cycle — not just before the due date — actually reduces your interest charge.
Understanding daily interest accumulation is the foundation for any smart debt payoff plan. See how much you'll pay over the full life of your balance with our credit card payoff calculator, or compare strategies using the debt avalanche calculator and the debt snowball calculator. If you're only making minimum payments, our minimum payment calculator shows the full long-term cost.
Credit cards use your Average Daily Balance multiplied by the Daily Periodic Rate (APR ÷ 365) multiplied by the number of days in the billing cycle. For example, a $4,000 balance at 22% APR over a 30-day cycle produces: $4,000 × (0.2299 ÷ 365) × 30 = $75.56 in interest. The key insight is that interest accrues daily — so making payments earlier in the month reduces the average daily balance and lowers your next statement's interest charge.
Your DPR is simply your APR divided by 365. For a 22% APR card, the DPR is 22 ÷ 365 = 0.0603% per day. This rate is applied to your balance each day of the billing cycle. Because interest is compounded daily, your effective annual rate is slightly higher than your stated APR — though the difference is small for most consumer balances. The DPR is the most accurate way to understand what you're paying on any given day.
Yes — most US credit cards compound interest daily. This means each day's interest is added to your balance, and the following day's interest is calculated on that slightly higher amount. In practice, the compounding effect on most consumer balances is modest — but it does mean your effective annual rate is slightly above your stated APR. For a 22% APR with daily compounding, the effective annual rate is approximately 24.6%.
Pay down your balance — the lower your balance, the less daily interest you accrue. Making payments earlier in the billing cycle reduces your Average Daily Balance for that month. You can also call your issuer and request a rate reduction; studies show issuers approve about 70% of rate reduction requests from customers with good payment histories. A balance transfer to a 0% APR promotional card is another strategy — use our main payoff calculator to figure out the exact monthly payment needed to clear the debt before the promotional period ends.
Last updated: June 2025