About Mortgage Affordability Calculator

Estimate how much home your income can support using the 28/36 guideline lenders commonly use

House hunting gets expensive fast when you fall in love with a home before you know what your income can actually support. This Mortgage Affordability Calculator flips the order: start with your gross annual income and monthly debts, then apply the 28/36 guideline that lenders commonly use as a first screen. The rule says housing costs should stay near 28 percent of gross monthly income, and total debts including the new housing payment should stay near 36 percent, so existing car payments, credit cards, and student loans directly reduce what is left for a mortgage. From the tighter of those two limits, the calculator subtracts your estimated monthly property taxes and homeowners insurance, because lenders count those as part of your housing cost, leaving a principal and interest budget. It then works backwards through the standard loan amortization formula at the rate and term you choose - 30, 20, or 15 years - to find the largest loan that budget can carry, and adds your down payment to estimate a maximum home price. Try it with debts paid down, a larger down payment, or a shorter term to see which lever actually moves your price range and monthly payment the most before you talk to a lender.

Who operates this site

Mortgage Affordability Calculator (mortgage.moneycalcworks.com) is operated by BrightSpan Holdings LLC under the Book AI Studio brand. Book AI Studio builds practical online calculators and tools that give people clear, honest estimates before they make a decision. If you have a question about this site, a correction to suggest, or a problem to report, contact us at admin@bookaistudio.com.

Ready to try it? Open the Estimate what you can afford tool.