YourFinanceCoach

Credit card interest calculator

Find out how long a card balance takes to clear, and how much of your repayments is interest.

The purchase rate on your card. US cards quote this as an APR.

How much do you pay each month?

Leave blank if you have stopped using the card.

Interest is charged

Most issuers apply a daily rate. Monthly uses the simpler APR ÷ 12.

Time to clear the balance

2 years 2 months

You would pay $775.92 in interest — 20.55% of everything you hand over.

Total interest
$775.92
Total repaid
$3,775.92
First month’s interest
$55.24

Charged before any of your payment reaches the balance.

Monthly rate
1.841198%

Implied by the APR.

Month-by-month breakdown (26 months)
Interest, payment and balance for each month
MonthOpeningInterestPaymentClosing
1$3,000.00$55.24$150.00$2,905.24
2$2,905.24$53.49$150.00$2,808.73
3$2,808.73$51.71$150.00$2,710.44
4$2,710.44$49.90$150.00$2,610.34
5$2,610.34$48.06$150.00$2,508.40
6$2,508.40$46.18$150.00$2,404.58
7$2,404.58$44.27$150.00$2,298.85
8$2,298.85$42.33$150.00$2,191.18
9$2,191.18$40.34$150.00$2,081.52
10$2,081.52$38.32$150.00$1,969.84
11$1,969.84$36.27$150.00$1,856.11
12$1,856.11$34.17$150.00$1,740.28
13$1,740.28$32.04$150.00$1,622.32
14$1,622.32$29.87$150.00$1,502.19
15$1,502.19$27.66$150.00$1,379.85
16$1,379.85$25.41$150.00$1,255.26
17$1,255.26$23.11$150.00$1,128.37
18$1,128.37$20.78$150.00$999.15
19$999.15$18.40$150.00$867.55
20$867.55$15.97$150.00$733.52
21$733.52$13.51$150.00$597.03
22$597.03$10.99$150.00$458.02
23$458.02$8.43$150.00$316.45
24$316.45$5.83$150.00$172.28
25$172.28$3.17$150.00$25.45
26$25.45$0.47$25.92$0.00

Fees, cash-advance rates and penalty rates are not included, and a promotional rate ending part-way through is not modelled. Paying the statement balance in full by the due date usually means no interest on purchases at all.

How this is worked out

Monthly interest = balance × [(1 + APR ÷ 365)^(365 ÷ 12) − 1]

What this assumes

A calculator is only as good as what it leaves out. These are the assumptions built into the result above.

  • Interest accrues daily by default, which is how most card issuers charge. Switch to monthly for the simpler APR ÷ 12 convention.
  • The APR is fixed. A promotional rate ending mid-way is not modelled.
  • Paying in full each month before the due date usually means no interest at all on purchases — this tool models a balance that is carried.
  • Fees, cash-advance rates and penalty rates are not included.

Educational information only. This page explains how something works in the United States. It is not financial advice and does not take account of your circumstances. Rates, fees and eligibility change without notice — check the provider’s own terms before you act.

For free, impartial guidance, see Consumer Financial Protection Bureau. To complain about a firm, contact the CFPB complaint database.

Guides that go with this tool

  • How Credit Card Interest Works

    Card interest is charged daily on an average balance, not monthly on the closing one. Understanding the grace period is what makes the difference between paying nothing and paying a lot.

  • Credit Card Minimum Payments: What They Really Cost

    The minimum payment is designed to keep an account current, not to clear it. Here is what that means in years and dollars.

  • Getting Out of Credit Card Debt

    A worked sequence for clearing card balances: stop the growth, know the real numbers, pick an order, and consider whether cheaper credit is available.