Loan Calculator

Guide: Loan Calculator

How a fixed-rate loan works

Most mortgages, car loans and personal loans use a level payment: the same amount every month. Each month the lender charges interest on the remaining balance, and the rest of your payment reduces the principal. Because the balance is highest at the start, early payments are mostly interest.

The formula

• Monthly rate: i = annual rate ÷ 12 ÷ 100
• Payment: PMT = P × i ÷ (1 − (1 + i)^−n), with n = years × 12 (for a 0% loan, PMT = P ÷ n)
• Each month: interest = balance × i; principal paid = PMT − interest; new balance = balance − principal

Example: 200,000 at 6% for 30 years gives a payment of 1,199.10 and about 231,676 of interest over the life of the loan.

Extra payments

Enter an amount in "Extra payment per month". It is added to every payment and applied to principal. The summary then shows the new payoff time, the interest saved and the time saved compared with paying the minimum only. Even a small extra amount early on can cut years off a long loan.

Notes

Payments are rounded to cents and the last payment clears the remaining balance. Lenders may round or start counting interest differently, and some loans charge prepayment fees, so treat this as a close estimate and confirm with your lender.

FAQ

How is the monthly payment calculated?

Payment = P × i ÷ (1 − (1 + i)^−n), where P is the loan amount, i the monthly rate (annual rate ÷ 12) and n the number of payments.

What is an amortization schedule?

A table of every payment showing how much goes to interest, how much reduces the principal, and the remaining balance. Early payments are mostly interest.

How do extra payments help?

Extra money goes straight to principal, so later interest is charged on a smaller balance. The loan ends sooner and total interest falls; the calculator shows both savings.

Does it include taxes, insurance or fees?

No. It covers principal and interest only. Add property tax, insurance or fees separately.

Can I download the schedule?

Yes. "Download CSV" creates a file on your device that opens in Excel, Numbers or Google Sheets.