About

We built Mortgage Calculators because a simple question — what will this home cost me each month? — should have a simple, honest answer. No sign-up, no paywall, no email needed just to see a number.

Who built this

This site is run by a small editorial team, listed on every page as the Mortgage Calculators Editorial Team. We are not a bank, not a lender, not a mortgage broker, and not a financial adviser. We built the tool we wanted to use ourselves: type in the home price and the rate, and see the full monthly payment — principal and interest, taxes, insurance, HOA dues and PMI — with the formula and the figures printed next to the result.

Why we built it

A home is the biggest purchase most people ever make, and the monthly payment is the number that decides whether it fits. At that moment, what you need is a straight number and the maths behind it. You do not need an account, a sales call, or a long article before the answer. That is the whole idea of this site. Every calculator on it is free, works in your browser, and shows its working. If a number is a rough estimate, the page says so in plain words, next to the number.

How the calculators work

Every calculation runs in your browser, on your own device. The numbers you type in are never sent to us, stored by us, or seen by anyone else. The monthly payment comes from the standard amortization formula: monthly rate r = annual rate / 12, n = years × 12, payment M = P × r × (1+r)ⁿ / ((1+r)ⁿ − 1), where P is the loan amount. Property taxes and insurance are split into 12 monthly parts and added on top. PMI is charged only when the down payment is under 20%, and it usually ends when the loan balance reaches 80% of the home value.

The affordability calculator uses the 28/36 rule of thumb: housing at no more than 28% of gross monthly income, and housing plus all debts at no more than 36%. The refinance calculator compares the old and new payments and divides the closing costs by the monthly saving to find the break-even point. Each tool page shows a worked example with real numbers, so you can see exactly what the tool does before you trust it with your own figures.

About the rates in the examples

The worked examples use rates such as 6.5% as examples only. They are not live market rates, not quotes, and not predictions. Rates change every day and depend on the lender, the loan type, your credit and the home. Always use the rate a lender quotes you, and type it into the calculator yourself.

How we check and update the figures

We check the formula and the method against the sources named on each page, and we update the site when the method changes. The rates in the examples are checked each January and refreshed if they no longer look like a fair example. If a reader tells us a figure looks wrong, we run the calculation again first and fix the page if we got it wrong. You can report a wrong figure on the Contact page — tell us the page, the numbers you typed in, and the result you saw, and we will check it.

What this site does not do

This site does not give financial advice, does not lend money, does not take loan applications, and does not talk to lenders for you. It does not store your figures, and it does not sell anything. The numbers are estimates from the standard formula and the numbers you type in. A lender's real quote will differ because the rate, fees, taxes and insurance depend on your credit, the home and the lender. If you need an exact answer, talk to a lender or a financial adviser — and bring the breakdown from this site with you.

Sources and method. Standard amortization formula: monthly rate r = annual rate / 12, n = years × 12, payment M = P × r × (1+r)ⁿ / ((1+r)ⁿ − 1). PMI usually ends when the loan balance reaches 80% of the home value (Consumer Financial Protection Bureau guidance). Affordability uses the 28/36 rule of thumb used by many lenders. Rates in examples are examples only, not live market rates. Results are estimates, not financial advice.

Estimate, not financial advice. This calculator uses the standard amortization formula and the numbers you type in. It is not a loan offer and not financial advice. A lender will check your credit, income and debts and quote its own rate and fees before you borrow.