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Credit Card Interest Calculator

See exactly how much interest you're paying, your true cost, and how faster payments or a balance transfer can save you thousands.

Reference table

Credit Card BalancePAYOFF DATETotal InterestTotal Amount Paid
100October 2026$1.91$101.91
200November 2026$3.89$203.89
250November 2026$5.81$255.81
500December 2026$17.64$517.64
750January 2027$35.69$785.69
1,000March 2027$61.33$1,061.33
1,250April 2027$94.03$1,344.03
1,500June 2027$134.39$1,634.39
2,000September 2027$240.43$2,240.43
2,500December 2027$383.40$2,883.40
3,000March 2028$567.57$3,567.57
4,000November 2028$1,085.49$5,085.49
5,000August 2029$1,857.70$6,857.70
7,500April 2032$5,794.71$13,294.71
10,000April 2040$22,480.70$32,480.70

Save on Interest

  • Pay your balance in full each month to avoid all interest charges — the grace period resets when you pay in full.
  • Even $50 extra per month on a $5,000 balance at 22% APR saves over $2,000 in interest and pays off 3 years faster.
  • Consider a 0% intro APR balance transfer card if you have good credit — you could save thousands during the intro period.
  • Make payments early in your billing cycle. Since interest compounds daily, paying earlier reduces your average daily balance.

How Credit Card Interest Works

Credit card interest is the cost you pay for carrying a balance from one billing cycle to the next. Unlike simple interest, credit card interest compounds daily — meaning you pay interest on interest every single day. Your card's APR (Annual Percentage Rate) is divided by 365 to get a daily periodic rate. Each day, that rate is applied to your current balance, and the resulting interest is added to what you owe. This daily compounding effect is why credit card debt grows so quickly and why even small balances can become expensive over time. The key insight is that if you pay your full statement balance by the due date every month, you pay zero interest — the grace period protects you. But the moment you carry any balance forward, interest starts accruing on everything immediately.

How This Calculator Works

Enter your current credit card balance, your card's APR, and the amount you plan to pay monthly. The calculator simulates your payoff journey using daily compounding interest, showing exactly how long it will take to reach zero and how much total interest you'll pay. It also calculates what would happen if you only made minimum payments — revealing the shocking true cost of the minimum payment trap. Unique metrics like the true cost multiplier show how much your original purchases actually cost after interest, while the daily interest cost makes the urgency real. If you toggle on the balance transfer comparison, it calculates whether transferring your balance to a lower-rate card would save you money after accounting for the transfer fee.

Key Factors Affecting Credit Card Interest

  • Daily Compounding: Interest is calculated daily and added to your balance. A $5,000 balance at 22% APR grows by $3.01 every single day.
  • Grace Period: If you pay your full statement balance by the due date, you pay zero interest on purchases. Carrying any balance eliminates this protection.
  • Minimum Payment Trap: Paying 2% minimum on $10,000 at 22% APR takes 27+ years and costs over $16,000 in interest — more than the original debt.
  • APR vs Daily Rate: Your APR divided by 365 gives your daily rate. At 22% APR, that's 0.0603% per day — small-sounding but devastating over time.
  • Multiple APRs: Many cards charge different rates for purchases, balance transfers, and cash advances. Cash advances (25–30%+) have no grace period.
  • Variable Rates: Most credit cards have variable APRs tied to the prime rate. When the Fed raises rates, your credit card rate rises automatically.

Credit Card Interest Rate Ranges

  • Excellent Credit (750+): 14–19% APR. The lowest standard rates available, but still expensive compared to other loan types.
  • Good Credit (700–749): 18–24% APR. The most common range for rewards cards. Even 'good' rates are high in absolute terms.
  • Fair Credit (650–699): 22–27% APR. Higher rates mean interest compounds faster — prioritize paying these balances aggressively.
  • Poor Credit (below 650): 25–30%+ APR. At these rates, a $5,000 balance costs $4+ per day. Consider debt counseling if struggling.
  • Store Cards: Typically 25–30% APR. Among the highest rates available — avoid carrying balances on store-branded cards.
  • Balance Transfer Cards: 0% intro APR for 12–21 months. Powerful tool for paying down debt, but watch the fee (3–5%) and post-intro rate.

Credit Card Interest Examples

Step-by-step examples showing how interest accumulates and the impact of different payment strategies

$5,000 Balance — Minimum vs Fixed Payment

  1. Balance: $5,000 at 22.99% APR
  2. Daily rate: 22.99% ÷ 365 = 0.0630% per day
  3. Day 1 interest: $5,000 × 0.000630 = $3.15
  4. First month interest: ~$95.79 (compounds daily)
  5. Minimum payment (2%): $100 → only $4.21 goes to principal!
  6. At minimum only: 32 years, $9,447 in interest
  7. At $200/month fixed: 32 months, $1,357 in interest
  8. Difference: save $8,090 and 29+ years!

Paying $200/mo instead of minimum saves $8,090 in interest and 29 years of payments

$10,000 Balance — Balance Transfer Comparison

  1. Current card: $10,000 at 24.99% APR, $300/mo
  2. Monthly interest (first month): ~$208
  3. Only $92 of $300 goes to principal
  4. Payoff at current rate: 50 months, $4,840 interest
  5. Balance transfer: 0% intro for 18 months, 3% fee
  6. Transfer fee: $10,000 × 3% = $300
  7. $300/mo for 18 months = $5,400 (pays off $5,100 net)
  8. Remaining $4,900 at new rate after intro period

Balance transfer saves ~$3,200 in interest if you can pay off most during the 0% intro period

Frequently Asked Questions

How is credit card interest calculated?

Credit card interest is calculated using daily compounding. Your APR is divided by 365 to get a daily periodic rate. Each day, that rate is multiplied by your current balance to determine that day's interest charge. This interest is added to your balance, so the next day you're paying interest on a slightly higher amount. At 22% APR, a $5,000 balance accrues about $3.01 per day in interest.

What is the true cost of minimum payments?

Minimum payments are designed to keep you in debt as long as possible. On a $5,000 balance at 22% APR, paying only the 2% minimum would take over 30 years and cost more than $9,000 in interest — nearly double the original balance. The minimum payment starts at $100 but shrinks as your balance decreases, meaning less and less goes to principal over time.

How can I avoid paying credit card interest?

Pay your full statement balance by the due date every month. This activates your grace period, which means no interest is charged on new purchases. If you already have a balance, you won't have a grace period until you pay it off completely. Consider setting up autopay for the full balance to ensure you never miss a payment and always avoid interest.

What is a good credit card interest rate?

Credit card rates are generally high compared to other loans. As of 2025–2026, rates range from about 14% for excellent credit to 30%+ for poor credit. A 'good' rate is below 18%, but even that is expensive for long-term borrowing. If you carry a balance regularly, a low-interest card (13–16% APR) or a 0% balance transfer card is worth considering.

Is a balance transfer worth it?

A balance transfer to a 0% intro APR card is worth it if: the interest savings exceed the transfer fee (typically 3–5% of the balance), you can pay off a significant portion during the intro period, and you won't rack up new debt. For example, transferring $8,000 with a 3% fee ($240) from a 24% APR card saves about $160/month in interest during the 0% period.

Why does my balance grow even though I'm making payments?

If your monthly payment is close to or less than the interest charged, very little goes toward reducing your actual balance. At 24% APR on a $10,000 balance, about $200/month goes to interest alone. If your payment is $210, only $10 reduces your balance — meaning it would take 83+ years to pay off. You need to pay significantly more than the interest portion to make real progress.

What is the difference between APR and daily rate?

APR (Annual Percentage Rate) is the yearly interest rate on your card. The daily periodic rate is your APR divided by 365. For example, 22% APR becomes 0.0603% per day. While 0.06% sounds tiny, it compounds every day — meaning you pay interest on yesterday's interest. Over a year, this daily compounding makes the effective rate slightly higher than the stated APR.

Does paying more than the minimum help that much?

Dramatically. On a $5,000 balance at 22% APR: minimum payments take 30+ years and cost $9,000+ in interest. Paying $150/month fixed takes 44 months and costs $1,538. Paying $300/month takes 19 months and costs $667. Every extra dollar above the minimum goes directly to principal, creating a snowball effect that accelerates your payoff.

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