Mortgage Calculator

Plan your home purchase with this free mortgage payment calculator. Type the home price, your down payment, the annual interest rate and the loan term in years, then press Calculate to see your monthly payment, the loan amount, the total interest and the total you will pay. Home buyers use it to compare loan offers and check what they can afford. Everything runs in your browser, so your numbers never leave your device.

Estimate only. This is not financial advice and not a loan offer.

How the monthly mortgage payment is worked out

The tool works out your loan from the price and down payment first.

Loan amount = home price – down payment.

Then it uses the standard loan payment formula for equal monthly payments:

Monthly payment = L x r / (1 – (1 + r) to the power of -n). Here L is the loan amount, r is the monthly interest rate (the annual rate divided by 12), and n is the number of monthly payments (the years times 12).

After that it adds the payments up:

  • Total paid = monthly payment x n.
  • Total interest = total paid – loan amount.

Solved example: a $200,000 home with $40,000 down at 6% for 30 years

  1. Loan amount = $200,000 – $40,000 = $160,000.
  2. Monthly rate = 6% / 12 = 0.5%. Number of payments = 30 x 12 = 360.
  3. Monthly payment = $160,000 x 0.005 / (1 – (1 + 0.005) to the power of -360) = $959.28.
  4. Total paid = $959.28 x 360 = $345,340.80.
  5. Total interest = $345,340.80 – $160,000 = $185,340.80.

So the buyer pays $959.28 each month and $185,340.80 in interest over the 30 years.

How to use this calculator

  1. Type the home price in dollars.
  2. Type your down payment, then the annual interest rate as a percent and the loan term in years.
  3. Press Calculate and read the monthly payment, the loan amount, the totals and the year-by-year balance.

Limits of this tool

  • This is an estimate only. It is not financial advice and not a loan offer.
  • It leaves out property tax, home insurance, private mortgage insurance and HOA fees, which are part of the real monthly housing cost.
  • It assumes a fixed interest rate with equal monthly payments. An adjustable rate changes over time.
  • A lender’s figures may differ, so check the full loan terms before you buy.

Frequently asked questions

What is a down payment, and how does it change my payment?

A down payment is the money you pay upfront when you buy a home. The rest is covered by the mortgage loan. A bigger down payment means a smaller loan, which lowers the monthly payment and the total interest. This tool needs a down payment below the home price, and it can be zero.

Does a bigger down payment always help?

Yes. A bigger down payment cuts the loan amount, so the monthly payment drops and the total interest falls too. In real life it can also help you avoid private mortgage insurance, but this tool does not add insurance or tax costs to the result.

Why is my lender’s quote different from this mortgage payment calculator?

Lenders usually quote the full monthly housing cost, which adds property tax, home insurance, private mortgage insurance and fees on top of the loan payment. This tool shows the pure loan math, which is best for comparing loan offers side by side.

Can I use this tool for a 15-year mortgage?

Yes. Just type 15 in the loan term field. A shorter term raises the monthly payment but cuts the total interest a lot, because the loan is paid off much sooner.

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