Credit Card APR Calculator
Free credit card APR calculator to find your Daily Periodic Rate (DPR), monthly interest charges, and effective APR. See the real cost of carrying a balance in 2025.
Credit Card APR Calculator
Enter your details below to calculate
Quick presets
Calculator Inputs
Check this if you pay the full statement balance by the due date (Grace Period).
Disclosed APR usually excludes fees. This "Effective APR" helps you compare total costs.
Calculated Interest
Interest This Billing Cycle
Based on 30 days
Daily Periodic Rate (DPR)
0.068%
Monthly Rate (Simple)
2.083%
Monthly Rate (Compound)
2.104%
Effective APR
24.99%
Cost of Carrying Balance
Estimated accumulated interest over 12 months (assuming constant balance)
How to Use This Calculator
Enter Your Average Daily Balance
Check your latest statement for the 'Average Daily Balance' figure, or estimate it by using your typical balance. This is the amount interest is charged on.
Input Your APR
Find the Annual Percentage Rate (APR) on your statement. It's usually between 15% and 29.99%. Enter this to calculate your Daily Periodic Rate (DPR).
Add Optional Fees
If your card has an annual fee or monthly maintenance fee, add it in the 'Optional Fees' section to see your 'Effective APR'—the true cost of the card.
Review Your Real Cost
See exactly how much interest you will pay this billing cycle. Use the chart to visualize how much interest accumulates over a year if the balance remains unpaid.
Key Features
Calculates Daily Periodic Rate (DPR) & Monthly Interest
Visualizes cost of carrying a balance over 12 months
Includes optional fees (Annual, Monthly, One-time) in Effective APR
Grace Period toggle to see savings from paying in full
Quick Presets for Low, High, and 0% APR cards
Mobile-friendly design with instant results
Understanding Your Credit Card APR in 2025
Credit card Annual Percentage Rate (APR) is one of the most misunderstood numbers in personal finance. While it is expressed as an annual rate (e.g., 24.99%), you don't pay interest annually. Instead, credit card issuers use a Daily Periodic Rate (DPR) to charge interest on your average daily balance every single day you carry debt.
In 2025, with the average credit card APR hovering near record highs (often exceeding 22%), understanding exactly how this cost accrues is critical. A seemingly small balance can balloon quickly due to daily compounding. This calculator breaks down that annual number into the daily cost that actually hits your wallet.
How Credit Card Interest is Calculated
Most issuers use the Average Daily Balance (ADB) method. Here is the step-by-step math that happens behind the scenes:
The Formula Chain
- Convert APR to DPR: Divide your APR by 365 (or 360, depending on the issuer).
24.99% ÷ 365 = 0.0684% per day - Calculate Daily Interest: Multiply your day's balance by the DPR.
$2,000 × 0.000684 = $1.37 interest for that day - Sum for the Cycle: Add up the interest charges for every day in the billing cycle (usually 30 days).
This "daily" calculation is why paying down your balance in the middle of the month saves you money compared to waiting until the due date. Every day the balance is lower, the daily interest charge drops.
Real-World Scenario: The Cost of Waiting
Let's look at a common scenario. You have a $5,000 balance on a rewards card with a 29.99% APR. You plan to pay it off, but money is tight.
Scenario A: Minimum Payment Only
You pay the minimum (~$150). Most of that goes to interest ($125). Your principal barely moves.
Scenario B: Aggressive Paydown
You pay $500/month. You attack the principal directly.
Our calculator shows you the "Interest This Cycle" to highlight exactly how much money you are throwing away each month just for the privilege of delaying payment.
Expert Tips to Lower Your Effective Rate
- •The "Grace Period" Loophole: If you pay your statement balance in full by the due date, most cards waive all interest for that cycle. This effectively gives you a 0% APR loan for 25-50 days.
- •Request a Rate Reduction: If you have a good payment history, call your issuer and ask for a lower APR. It works more often than you think.
- •Balance Transfer Strategy: Move high-interest debt to a card with a 0% intro APR (usually for 12-18 months). Just be sure to factor in the transfer fee (typically 3-5%) using our calculator's fee section.
Common APR Mistakes
Confusing APR with APY
APR is the simple interest rate you pay. APY (Annual Percentage Yield) includes compounding. For investments, you want high APY. For debt, you want low APR. Credit cards technically charge simple interest daily, but the effect feels like compounding if you let the interest capitalize.
Ignoring Cash Advance Rates
Using your credit card at an ATM usually triggers a much higher "Cash Advance APR" immediately. There is no grace period—interest starts ticking the second the cash dispenses.
Related Tools
If this APR calculator revealed a scary number, use these tools to make a plan:
- Credit Card Payoff Calculator: See exactly how long it will take to be debt-free at your current payment level.
- Balance Transfer Calculator: Calculate if moving your debt to a new card is worth the transfer fee.
- Debt Avalanche Calculator: Optimize your payments to save the most interest possible across multiple cards.
About the Author
Marko Hrvojević
Finance Expert, CPA with 12+ years in financial analysis and tax planning
Connect with MarkoFrequently Asked Questions
How is credit card interest actually calculated?
Most issuers use the Average Daily Balance (ADB) method. They take your APR, divide it by 365 to get a Daily Periodic Rate (DPR), and multiply that by your balance for every day in the billing cycle. Then they sum those daily charges. The formula is roughly: Interest = ADB × (APR/365) × Days in Cycle.
What is a Daily Periodic Rate (DPR)?
DPR is your APR broken down to a daily level. For a 24% APR, the DPR is approx 0.0657% (0.24 ÷ 365). It might look small, but it compounds daily, which is why credit card debt grows so fast.
Does paying the minimum cover the interest?
Barely. On high-balance cards, the minimum payment is often set as 'Interest + 1% of Principal'. This means your balance decreases very slowly. Paying only the minimum is the most expensive way to manage debt.
What is the 'Grace Period'?
The grace period is a window (usually 21-25 days) between the statement closing date and the due date. If you pay your statement balance in full by the due date, the issuer waives interest on new purchases. If you carry a balance, you lose this grace period.
Why is my Effective APR higher than my APR?
Our calculator's 'Effective APR' adds fees (annual fees, etc.) to the interest cost to show you the total annualized cost of borrowing. If you have a $100 annual fee and a low balance, that fee effectively acts like a massive interest rate hike.
Related Calculators
Explore more tools in Credit & Debt Management
APR Calculator: Calculate True Loan Cost & Effective Rate (2025)
Free APR calculator that reveals the true cost of loans by including interest rates, points, and fees. Compare loan offers accurately with our 2025 APR tool.
Auto Loan APR Calculator: True Cost of Vehicle Financing
Free auto loan APR calculator reveals the true cost of vehicle financing including interest rates, origination fees, documentation fees, and all charges. Compare loan offers accurately with real APR calculations.
Balance Transfer Calculator: 0% APR Savings & Fees
Estimate savings with our balance transfer calculator. Compare 0% APR offers, include transfer fees, and see if moving your balance makes sense for your plan.
Credit Card Interest Calculator: Daily & Monthly Charges (2025)
Calculate your exact credit card interest using the Average Daily Balance (ADB) method. See how paying early saves money and visualize daily compounding.
Credit Card Minimum Payment Calculator: Payoff Time & Interest (2025)
Calculate exactly how long it will take to pay off your credit card with minimum payments. See total interest costs and find a faster debt-free date.
Credit Card Payment Calculator: Monthly Payment Estimates
Use our credit card payment calculator to estimate your monthly payment. Enter balance, APR, and payoff goal to see costs and pick a plan that fits your budget.