Mortgage Calculator

Estimate your monthly payment, including optional tax and insurance.

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Example

A $300,000 loan at 6.5% for 30 years has a monthly principal and interest payment of about $1,896.20 and about $382,633 of total interest over the life of the loan.

How the monthly mortgage payment is calculated

For a fixed-rate loan, the monthly principal and interest payment is M = L × i × (1 + i)^N / ((1 + i)^N - 1). L is the loan amount, i is the monthly interest rate (the annual rate divided by 12) and N is the number of monthly payments (years × 12). Early payments are mostly interest, and the share that repays principal grows every month.

What is included in this estimate

  • Principal and interest: the part that repays the loan, based on the home price minus your down payment, the rate and the term.
  • Property tax and home insurance: optional. Enter the yearly amounts and the calculator divides them by 12 and adds them to the monthly total.
  • Not included: private mortgage insurance (PMI), HOA fees, closing costs and utilities. Lenders often require PMI on conventional loans when the down payment is under 20% of the price, so your real payment may be higher.

Worked example

A $400,000 home with $80,000 down leaves a $320,000 loan. At 6.5% for 30 years, i = 0.065 / 12 = 0.005417 and N = 360. That gives a principal and interest payment of about $2,022.62 per month. Over 30 years you would pay about $408,142 in interest on top of the $320,000 borrowed.

How the term changes the cost

A shorter term means a higher monthly payment but much less total interest. For a $300,000 loan at 6.5%, a 30-year term costs about $1,896.20 per month and $382,633 in total interest. A 15-year term costs about $2,613.32 per month and $170,398 in total interest.

Ways to lower your payment

  • Make a larger down payment, which reduces the loan amount.
  • Compare rates from several lenders. Even a quarter of a percentage point changes the payment.
  • Choose a longer term if you need a lower monthly payment, knowing that total interest will be higher.
  • Improve your credit score before applying, because it affects the rate you are offered.

Related calculators

For other loan types, use the loan calculator. To see how savings grow while you save for a down payment, try the compound interest calculator.