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Mortgage Calculator

Enter your home price, down payment, loan term, and interest rate. Get your monthly payment, total interest, and a complete amortization schedule — in under a minute.

What you'll need

  • Home purchase price
  • Down payment amount (or percentage)
  • Loan term — 15, 20, or 30 years
  • Expected interest rate

What you'll get

Monthly payment

Principal + interest

Total interest

Over the life of the loan

Total cost

What you actually pay

Amortization schedule

Year-by-year breakdown

How the mortgage payment formula works

The standard fixed-rate mortgage payment is calculated using the amortization formula:

M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1]
  • M = Monthly payment
  • P = Loan principal (home price minus down payment)
  • r = Monthly interest rate (annual rate ÷ 12)
  • n = Total number of payments (years × 12)

How It Works

1

Enter loan details

Input your home price, down payment, interest rate, and loan term.

2

See your payment

Get your monthly principal & interest payment instantly with a full amortization breakdown.

3

Adjust and compare

Change rates, terms, or down payment amounts to find the scenario that fits your budget.

Monthly Payments by Loan Amount & Rate

Loan Amount6.5% / 30yr7.0% / 30yr6.5% / 15yr
$200,000$1,264$1,331$1,742
$300,000$1,896$1,996$2,613
$400,000$2,528$2,661$3,484
$500,000$3,160$3,327$4,355

Principal & interest only. Does not include taxes, insurance, or PMI.

Frequently asked questions

How do you calculate a monthly mortgage payment?

Use the formula M = P[r(1+r)^n]/[(1+r)^n-1] where P is the loan principal (home price minus down payment), r is the monthly interest rate (annual rate ÷ 12), and n is the total number of monthly payments (loan term in years × 12).

What is a good down payment for a house?

20% is the traditional benchmark — it lets you avoid Private Mortgage Insurance (PMI). However, many loan programs allow as little as 3–5% for first-time buyers. A larger down payment reduces your monthly payment and total interest paid.

What is the difference between a 15-year and 30-year mortgage?

A 15-year mortgage has higher monthly payments but you pay significantly less interest over the life of the loan and build equity faster. A 30-year mortgage has lower monthly payments, giving you more flexibility, but you pay more total interest.

Does the monthly payment include taxes and insurance?

This calculator shows principal and interest only. Your actual monthly mortgage bill (PITI) also includes property taxes, homeowners insurance, and possibly PMI. Add roughly 0.5–1.5% of the home value annually to estimate those costs.

Ready to see your numbers?

Calculate My Mortgage →