Mortgage Calculator
Estimate your monthly mortgage payment, the total interest you'll pay, and the overall cost of the loan.
| Home price | |
| Down payment | |
| Loan term | years |
| Interest rate | % per year |
Result
Your payment estimate will appear here.
How this calculator works
A mortgage payment (principal and interest) is calculated like a fixed-rate loan: you repay the amount borrowed over a set number of years with equal monthly payments.
Formula
- Loan amount P = home price − down payment
- Monthly rate r = annual interest rate ÷ 12; payments n = years × 12
- Payment M = P × r × (1+r)n ÷ ((1+r)n − 1). If r = 0, M = P ÷ n.
- Total interest = M × n − P.
Worked example
$350,000 home with $70,000 down means borrowing $280,000. At 6.5% for 30 years (360 payments), the principal-and-interest payment is about $1,769.91/month, with roughly $357,167 total interest over the life of the loan (figures rounded).
What this includes (and what it doesn’t)
- Included: principal and interest.
- Not included: property taxes, homeowners insurance, mortgage insurance (PMI), HOA fees, points, or closing costs — your real monthly cost can be higher.
Estimate for general information only, not financial advice. Confirm details with your lender.
How to use the Mortgage Calculator
It takes a few seconds, and every figure is calculated in your browser.
- Enter the home price.
- Enter the down payment.
- Enter the loan term.
- Enter the interest rate.
- Press Calculate — the result appears in the dark panel beside the form.
- Use Copy, CSV, Share or Print under the result if you want to keep it.
Mortgage Calculator — frequently asked questions
What formula does the Mortgage Calculator use?
Loan amount P = home price − down payment Monthly rate r = annual interest rate ÷ 12; payments n = years × 12 Payment M = P × r × (1+r) n ÷ ((1+r) n − 1). If r = 0, M = P ÷ n. Total interest = M × n − P.
How does the Mortgage Calculator work?
A mortgage payment (principal and interest) is calculated like a fixed-rate loan: you repay the amount borrowed over a set number of years with equal monthly payments.
Can you walk through a worked example?
$350,000 home with $70,000 down means borrowing $280,000. At 6.5% for 30 years (360 payments), the principal-and-interest payment is about $1,769.91/month, with roughly $357,167 total interest over the life of the loan (figures rounded).
Last updated 10 November 2026 · Formula, worked example and assumptions are documented above, and every result is calculated in your browser.