Enter your annual income, monthly debt payments, and down payment above, and you’ll see the maximum home price the classic 28/36 rule supports — the same debt-to-income logic underwriters start from. It’s free, there’s no signup, and every calculation runs in your browser.
How to use
- Annual gross income — your household income before taxes and deductions.
- Monthly debt payments — car loans, student loans, and minimum card payments. Don’t include rent (you’re replacing it) or utilities.
- Down payment — the cash you’ll put toward the purchase.
- Interest rate and term — the rate you’ve been quoted and the loan length, typically 30 years.
The result shows your maximum home price, the loan behind it, and the monthly housing budget that produced both. The address bar updates as you type — copy the URL to save a scenario or compare a few side by side.
What the 28/36 rule actually says
The rule sets two ceilings. The front-end cap says your housing payment should stay under 28% of gross monthly income. The back-end cap says all debt payments together — housing plus everything else — should stay under 36%. Your real budget is whichever cap is lower, which is why existing debts matter so much: on a $10,000 gross month, $500 of debt payments leaves the 28% cap binding at $2,800, but $2,000 of debt payments drops the budget to $1,600. Paying off a car loan can add more buying power than a year of saving. If you’re debt-free, the 28% cap always binds, and only income and rate move your number. The result panel shows both caps so you can see which one is constraining you. Once the monthly budget is known, the calculator inverts the same annuity formula our mortgage payment calculator uses, converting dollars-per-month into a loan amount at your rate and term.
Lenders will often approve more — that’s not the same as affordable
Preapproval letters routinely exceed the 28/36 result, because many programs allow back-end ratios of 43% or more. But a preapproval measures default risk to the lender, not comfort for you: it knows nothing about childcare, retirement savings, or the fact that your roof is fifteen years old. Treat the 28/36 number as the budget that leaves room for the rest of your life, and anything above it as a decision to make deliberately — not a green light. Rate matters too: the same $2,800 budget supports about $46,000 more loan at 6% than at 7%, which is why it pays to compare offers before you settle on a price range.
Limits
This is a rule-of-thumb screen, not a preapproval. The housing budget covers principal and interest only — property taxes, homeowners insurance, PMI, and HOA dues all count against the 28% cap in real underwriting, so your practical maximum is lower, especially in high-tax areas. A reasonable adjustment is to subtract your local monthly tax-and-insurance estimate from the housing budget before reading off the price. Credit score, cash reserves, and employment history also shift what lenders offer. Once you have a target loan, see the true month-by-month cost with the amortization schedule calculator, and if you’re weighing an existing loan against today’s rates, the refinance break-even calculator shows when switching pays off. The CFPB’s debt-to-income guide explains how lenders view these ratios.
Browse all our calculators — each one shows its formula and sources. Our file-based tools run privately in your browser too.