Loan Calculator

What it does

A loan with equal payments is the same sum repeated: each month interest is charged on what you still owe, and whatever is left of the payment reduces the debt. Early on almost all of it is interest, which is why the balance barely moves for the first years and then falls quickly. The payment itself comes from one formula — the amount, the monthly rate and the number of months — and everything else follows from it.

How to use it

1. Type the amount you want to borrow.
2. Type the annual interest rate, and the term in years or months.
3. Read the monthly payment, the total you would repay and how much of that is interest.

The arithmetic runs in your browser. Nothing you type is sent anywhere and nothing is stored, so you can use these with real numbers.

Frequently asked questions

Why is there no currency symbol?
Because the arithmetic is the same in every currency, and picking one would make the page wrong for everyone else. Type the amount in whatever you use and read the answer in the same unit.

Does this include fees, insurance or taxes?
No. It is the interest on the loan and nothing else. Real offers add arrangement fees, insurance and sometimes taxes, which is why an advertised rate and the rate you end up paying are rarely the same number.

Why does the balance barely move at first?
Because interest is charged on what you still owe, and at the start you owe almost everything. On a thirty-year loan at six percent, the first payment is more than eighty percent interest. Halfway through the term you have paid well over half the money but nowhere near half the debt.

What if the rate is zero?
Then the payment is just the amount divided by the number of months, and the total repaid equals what you borrowed. The usual formula divides by zero there, so this page handles it separately — interest-free instalments are common enough to matter.

Wikipedia — Amortization schedule
Wikipedia — Compound interest
Wikipedia — Annual percentage rate
Wikipedia — Mortgage loan