Credit Card Interest Calculator
Enter your balance and APR to see how much credit card interest you are charged per day and per billing cycle. Add a monthly payment to see how long it takes to pay off the card and the total interest.
Free · No sign-up · Runs in your browser · Last reviewed November 2026
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About the Credit Card Interest Calculator
Credit card interest is charged daily on your balance at the daily periodic rate (APR divided by 365). This calculator shows the interest per day and per billing cycle with daily compounding, and how a fixed monthly payment changes the payoff time and total cost.
How to use it
- Enter your current card balance and the APR shown on your statement.
- Set the days in your billing cycle (usually 28 to 31) and, optionally, the amount you pay each month.
- Read the daily interest, the interest for the cycle and the payoff time with total interest.
How credit card interest is calculated
Daily periodic rate = APR ÷ 365. Each day the issuer multiplies your balance by that rate and adds the interest to the balance, so it compounds daily. Interest for the cycle is charged on your average daily balance.
Example: $5,000 at 24% APR. Daily rate = 24% ÷ 365 = 0.0658%. Daily interest = $3.29. Over a 30-day cycle with daily compounding that is about $99.58.
Monthly credit card interest by balance and APR
Interest for one 30-day billing cycle with daily compounding and no new purchases or payments:
| Balance | 18% APR | 21% APR | 24% APR | 27% APR | 30% APR |
|---|---|---|---|---|---|
| $500 | $7.45 | $8.70 | $9.96 | $11.22 | $12.48 |
| $1,000 | $14.90 | $17.41 | $19.92 | $22.43 | $24.95 |
| $2,000 | $29.80 | $34.81 | $39.83 | $44.86 | $49.91 |
| $3,000 | $44.70 | $52.22 | $59.75 | $67.29 | $74.86 |
| $5,000 | $74.50 | $87.03 | $99.58 | $112.16 | $124.77 |
| $7,500 | $111.76 | $130.54 | $149.36 | $168.24 | $187.15 |
| $10,000 | $149.01 | $174.05 | $199.15 | $224.31 | $249.54 |
| $15,000 | $223.51 | $261.08 | $298.73 | $336.47 | $374.30 |
| $20,000 | $298.02 | $348.10 | $398.31 | $448.63 | $499.07 |
How long it takes to pay off $5,000 at 24% APR
The same balance costs very different amounts depending on the monthly payment:
| Monthly payment | Months to pay off | Total interest |
|---|---|---|
| $125 | 82 months (6.8 years) | $5,159 |
| $150 | 56 months (4.7 years) | $3,322 |
| $200 | 36 months (3.0 years) | $2,001 |
| $250 | 26 months (2.2 years) | $1,449 |
| $300 | 21 months (1.8 years) | $1,143 |
| $400 | 15 months (1.2 years) | $812 |
| $500 | 12 months (1.0 years) | $635 |
Ways to pay less interest
- Pay the statement balance in full to keep the grace period on new purchases.
- Pay earlier in the cycle: interest accrues daily, so every day counts.
- Pay more than the minimum; extra payments go to principal.
- Ask for a lower APR or move the balance to a 0% balance transfer card and pay it off during the promotion.
- Consolidate with a lower-rate personal loan: compare with the debt consolidation calculator.
Frequently asked questions
How is credit card interest calculated?
Divide your APR by 365 to get the daily periodic rate, multiply it by your balance each day and add up the days in the billing cycle. With a $5,000 balance at 24% APR the daily rate is 0.0658%, about $3.29 a day and about $99.58 for a 30-day cycle.
How much interest will I pay on $5,000 at 24% APR?
About $99.58 a month and about $1,200 a year if the balance stays at $5,000. Paying $200 a month, it takes 36 months to pay off and costs about $2,000 in interest.
How much is 25% APR on $1,000?
A $1,000 balance at 25% APR costs about $0.68 a day, or about $20.75 in a 30-day billing cycle.
What is a daily periodic rate?
It is your APR divided by 365 (some issuers use 360). A 24% APR is a daily periodic rate of 0.0658%. Issuers apply it to your balance every day, so interest compounds daily.
How can I avoid credit card interest?
Pay the full statement balance by the due date every month. Most cards then give a grace period on new purchases, so you pay no interest. Cash advances and balance transfers usually have no grace period.
Does paying the minimum reduce interest?
Only slightly. Minimum payments mostly cover interest, so the balance falls slowly. See how long it takes with the minimum payment calculator or plan a fixed payment with the payoff calculator.
Official sources
Last reviewed: November 2026. Estimates only. Issuers may use a 360-day year, different compounding or minimum interest charges.