Loan calculator

Know three of the four numbers in a loan? This finds the fourth: the payment, the amount, the rate or the time it takes.

What do you want to find?
What you know
Loan term

How it’s worked out

Interest rate
Formula
With your numbers

Where your payments go

Principal and interest paid in each year of the loan. Early on, most of each payment is interest.

  • Principal
  • Interest

Amortization schedule

Show the schedule

Four numbers, one relationship

Every fixed-rate loan ties together the amount borrowed, the interest rate, the number of payments and the payment itself. Change any one and at least one other has to move: a longer term lowers the payment, and a lower rate lets the same payment support a bigger loan.

Questions people ask

How is a loan payment calculated?

For a fixed-rate loan paid monthly, the payment is P × r ÷ (1 − (1 + r)−n), where P is the amount borrowed, r is the annual rate divided by 12, and n is the number of monthly payments. The worked solution fills in your numbers.

Can I work out the interest rate from my payment?

Yes. Choose “Interest rate”, then enter the amount, the payment and the term. There is no direct formula for the rate, so the calculator narrows it down numerically until the payment matches to a fraction of a cent.

Is APR the same as the interest rate?

Not quite. APR includes certain fees spread over the loan, so it is usually a little higher than the note rate. Use the APR when comparing offers.