How to use it
- Type the card balance and the yearly interest rate: the monthly rate on your statement times 12.
- Choose how you pay: a fixed payment each month, or the minimum payment rule.
- For a fixed payment enter the monthly amount. For the minimum rule enter the share of the balance and the smallest minimum.
- Read the time to pay off and the total interest, then open the table to see how the balance falls each month.
How the balance falls each month
Each month the bank adds interest to the balance: the balance times the yearly rate, divided by 12. Your payment is taken from the balance plus that interest. The balance only falls when the payment is larger than the month's interest, so the payment decides whether the debt ever ends.
The last payment is the balance left plus its interest, which is smaller than the regular payment.
I = B × r ÷ 12
B next month = B + I − P
B balance at the start of the month
r yearly rate
I interest for the month
P payment- If the payment is not larger than the interest, the balance does not fall. The calculator stops and asks for a larger payment.
- Interest is rounded to the cent each month, as the bank does.
Why minimum payments take so long
A minimum payment is a small share of the balance, with a floor. It is set so that most of it goes to the interest. The balance falls slowly, and the interest keeps being charged on what remains, so the total interest can be much larger than the amount you borrowed.
In the worked example below, a minimum of 5% with a floor of 300 costs 9,893.19 in interest over 64 months. A fixed payment of 1,000 costs 5,258.02 over 26 months.
The rate on a card statement
Banks quote card interest in different ways. Many statements show a monthly rate: multiply it by 12 to get the yearly rate. A monthly rate of 1.86% is about 22.36% a year. Taxes and fees that your statement adds are not included, so the amount due can be higher than the figure here.
The default rate, 22.36% a year, is the Federal Reserve's figure for credit card accounts that were charged interest at commercial banks in the third quarter of 2026 (preliminary). Your card agreement and statement set the rate and the minimum payment that apply to you; check them, because rates and fees change.
What this calculator does not include
- Fees, late payment charges and the interest on cash advances, which have their own rates.
- New purchases on the card while you pay it off. Enter the balance you want to clear, or run the calculator again with the new balance.
- A rate that changes during the payoff.
Worked example: 20,000 at 22.36% a year, 1,000 a month
The monthly rate is 22.36% ÷ 12 = 1.86%. In the first month the interest is 20,000 × 22.36% ÷ 12 = 372.67, so only 627.33 of the 1,000 payment reduces the balance, which falls to 19,372.67.
The interest falls as the balance falls. After 25 payments of 1,000, the last payment is 258.02 with interest of 4.72. The payoff takes 26 months, which is 2 years and 2 months, with 5,258.02 of interest and 25,258.02 paid in total.
With a minimum payment of 5% of the balance and at least 300, the same card takes 64 months, with 9,893.19 of interest.
| Figure | |
|---|---|
| Fixed payment of 1,000: time to pay off | 2 years 2 months |
| Fixed payment of 1,000: total interest | 5,258.02 |
| Fixed payment of 1,000: total paid | 25,258.02 |
| Minimum of 5% (at least 300): time to pay off | 5 years 4 months |
| Minimum of 5% (at least 300): total interest | 9,893.19 |
Frequently asked questions
Why does a minimum payment take so long?
The minimum is a small share of the balance, so most of it goes to interest in the early months. The balance falls slowly and the interest keeps being charged on what remains.
How do I get the yearly rate from my statement?
Take the monthly interest rate shown on the statement and multiply it by 12. A monthly rate of 1.86% is about 22.36% a year, which is the rate the calculator starts with.
Why does the calculator say the payment does not cover the interest?
If the payment is not larger than the month's interest, the balance would not go down and the card would never be paid off. Raise the payment above the monthly interest.
Is the result the amount my bank will charge?
Not exactly. Banks add their own rounding, fees and the taxes on interest, and the rate can change. The statement and the bank's figures are the binding amounts.
Can I use it for a store card or a personal loan?
Yes, if you pay a fixed amount each month and the interest is charged monthly. For a loan with equal installments, the loan amortization calculator is a better fit.
Are my figures stored?
No. The calculation runs in your browser and nothing you enter is sent to us.
Sources
Figures and text last checked on Friday, November 13, 2026.