Free Mortgage Calculator (+ Guide)

What is a mortgage calculator?

A mortgage calculator works out the monthly cost of a home loan and how it's paid down over the years. This one counts every part of the monthly payment, often called PITI.

Your lender often collects tax and insurance with the loan payment, so this is closer to what leaves your account each month.

How to use the mortgage calculator

Have the home price and your down payment ready, and a tax estimate if you have one.

Your numbers stay in this browser, and the rate updates each week from Freddie Mac's survey.

A worked example

Here's the example the calculator loads when you press Try an example, worked out in October 2026.

You buy a $420,000 home with $42,000 down, which is 10%. You borrow $378,000 at 7% for 30 years, with $4,800 a year of property tax, $1,800 of insurance and PMI at 0.5% of the loan a year.

Your first payment sends $2,205 to interest and only $309.84 to the loan. Over 30 years, you'd pay $527,344 of interest.

PMI stops after 115 months, when you owe 78% of the price, having cost $18,113. All in, with the down payment, tax, insurance and PMI, the home costs $1,163,456 over 30 years.

How the term changes the cost

A shorter term has a bigger payment and far less interest. Here's the same $378,000 at 7%.

The 15-year loan costs $882.73 more a month and saves $293,781 of interest. Shorter terms often come with a lower rate too: 6.42% against 7.03% for a 30-year in Freddie Mac's latest survey.

How the rate changes the cost

One point of rate on a 30-year loan changes the payment by about $250 a month here.

Get quotes from a few lenders on the same day, and put each rate in the calculator.

How the down payment changes the cost

A bigger down payment lowers the loan and the PMI. Here's the same home at 7%.

At 20% down there's no PMI at all, which is where PMI stops on a conventional loan.

When PMI ends

Under the US Homeowners Protection Act, your lender must end PMI automatically when your loan is scheduled to reach 78% of the home's original value. You can ask to cancel it at 80%, and the CFPB explains how.

The calculator ends PMI when your balance reaches 78% of the price. Extra payments get you there sooner, so add one and watch the PMI date move.

Mistakes to avoid

These are the ways a mortgage ends up costing more than planned.

• Budgeting for principal and interest only, without tax and insurance
• Looking at the payment instead of the total interest
• Taking the first rate offered without comparing lenders
• Forgetting PMI under 20% down
• Spending every dollar of your budget, with nothing left for repairs

Run the full monthly cost through your budget before you look at homes.

Who is the mortgage calculator for?

It's for anyone buying a home or weighing a refinance, and these tools help with what comes after.

• Mortgage payoff calculator – for owning your home sooner with extra payments
• Loan calculator – for any other loan with a fixed rate
• Net worth calculator – for seeing your home equity grow
• Golden visa finder – for buying property that comes with residency
• Tax rates by country – for comparing where to buy

Work out the full cost here, then plan how to pay it off sooner.

More money calculators

Your currency and scene come with you to each one.

Once you own the home, the mortgage payoff calculator shows what every extra payment is worth.