How do I calculate a monthly loan payment?

Use the amortisation formula: P × r ÷ (1 − (1 + r)^−n), where r is the monthly rate and n the number of payments. The calculator applies it for you.

How much interest will I pay in total?

Multiply the monthly payment by the number of payments and subtract the amount borrowed.

Why do early payments reduce the balance so slowly?

Interest is charged on the outstanding balance, which is largest at the start. More of each early payment goes to interest.

Is this the same as an APR calculation?

No. It uses the nominal interest rate and excludes fees. APR includes some costs, so it is usually higher.

Loan Payment Calculator

Estimate the monthly payment, total interest and yearly balance of a fixed-rate loan.

Updated September 19, 2026Checked by the editorial team

Loan amount

Currency symbol

Interest rate (nominal, per year)

Term

Monthly payment

$489.15

Total repaid: $29,349.22
Total interest: $4,349.22
Number of payments: 60
Interest as share of amount borrowed: 17.4%

Payment = P × r ÷ (1 − (1 + r)^−n), with r = 0.5417% per month and n = 60. Fees, insurance and taxes are not included.

Year-by-year breakdown

Year	Principal paid	Interest paid	Balance
1	$4,373.62	$1,496.23	$20,626.38
2	$4,666.53	$1,203.32	$15,959.86
3	$4,979.05	$890.79	$10,980.81
4	$5,312.51	$557.34	$5,668.30
5	$5,668.30	$201.55	$0.00

Enter the amount borrowed, the annual interest rate and the term, and the calculator estimates the monthly payment, the total you will repay and how much of that is interest. A year-by-year table shows how the balance falls.

It fits any loan with equal monthly payments and a fixed rate, including car loans, personal loans and simple mortgage estimates. It does not include fees, insurance, taxes or a variable rate.

How loan payment calculator works

Each month the interest is the outstanding balance times the monthly rate. The payment is set so that, after the last instalment, the balance is exactly zero. Early payments are mostly interest, and later ones are mostly principal.

Terms can be entered in years or months. The rate is the nominal annual rate and is divided by 12 for the monthly rate. It is not an APR, which includes fees.

The formula

Payment  =  P × r ÷ (1 − (1 + r)^−n)
P = amount borrowed,  r = annual rate ÷ 12,  n = number of monthly payments
If the rate is 0:  Payment = P ÷ n

Worked example: 10,000 at 6% over 36 months

r = 0.06 ÷ 12 = 0.005 and n = 36.

Payment = 10,000 × 0.005 ÷ (1 − 1.005^−36) = 304.22.

Total repaid: 304.22 × 36 = 10,951.90, so interest is 951.90.

A larger example: 250,000 at 6.5% over 30 years is about 1,580.17 a month, or 318,861 in interest.

When to use this tool

Comparing loan offers with different terms and rates.
Seeing how much a longer term lowers the payment and raises the interest.
Budgeting for a car or personal loan.
Getting a first estimate of a mortgage principal and interest payment.

Common mistakes to avoid

Comparing only the monthly payment. A longer term lowers it but usually costs much more in total.
Entering the APR as the interest rate, or ignoring fees the lender adds.
Forgetting property tax and insurance on a mortgage. They are not included here.

Frequently asked questions

How do I calculate a monthly loan payment?: Use the amortisation formula: P × r ÷ (1 − (1 + r)^−n), where r is the monthly rate and n the number of payments. The calculator applies it for you.
How much interest will I pay in total?: Multiply the monthly payment by the number of payments and subtract the amount borrowed.
Why do early payments reduce the balance so slowly?: Interest is charged on the outstanding balance, which is largest at the start. More of each early payment goes to interest.
Is this the same as an APR calculation?: No. It uses the nominal interest rate and excludes fees. APR includes some costs, so it is usually higher.

Learn more

Results are for information only and are not financial, legal or medical advice. The calculation logic is covered by automated tests, and examples on this page are worked out and re-checked before publishing. Spotted a mistake? Tell us.