How much house can I afford?

What is the 28/36 rule?

The 28/36 rule is a two-part guideline lenders use to size up how much mortgage a borrower can safely handle. The 28% front-end ratio limits your total monthly housing payment (principal, interest, property tax, and insurance, often shortened to PITI) to 28% of your gross monthly income, the amount you earn before taxes. The 36% back-end ratio limits ALL of your monthly debt payments combined, housing plus car loans, student loans, credit cards, and anything else that shows up on a credit report, to 36% of that same gross income. Whichever ratio produces the smaller dollar amount is the one that actually constrains you.

The Consumer Financial Protection Bureau (CFPB), the federal agency that regulates consumer lending, publishes a version of this guideline in its "Your Money, Your Goals" financial toolkit: it recommends a mortgage debt-to-income ratio of 28 to 35 percent, and a total debt-to-income ratio of 36 percent or less, noting that some lenders go up to 43 percent or higher on the total. The flat "28%" figure most calculators and lenders quote sits at the conservative end of that CFPB range, and it is the number this calculator uses for the front-end limit.

Why do lenders use the 28/36 rule?

Lenders use debt-to-income ratios because they are one of the best available predictors of whether a borrower can keep making payments through a job loss, a rate reset, or an unexpected expense. A payment that eats a smaller share of income leaves more room to absorb a shock without missing a payment. The 36% back-end cap in particular exists because a lender cares about your total debt load, not just the mortgage, since car payments and student loans compete for the same paycheck as the house payment does. Federal mortgage rules build on the same logic: the CFPB's Qualified Mortgage standard originally capped debt-to-income at 43% for loans that get certain legal protections, and it has since moved to a rate-based test instead of a flat ratio, but the underlying idea, that a heavily indebted borrower is a riskier borrower, has not changed.

Calculate how much house you can afford

Enter your own numbers. The default combined tax and insurance rate is an editable estimate, not a verified figure for your area; check your county's property tax rate and get an actual homeowners insurance quote to refine it.

Math: max housing payment = the smaller of (28% × gross monthly income) and (36% × gross monthly income minus other debts). That payment funds principal, interest, tax, and insurance together, and since tax and insurance are a percentage of the home's price, the loan amount is solved directly: loan = (max housing payment minus (tax+insurance rate × down payment)) ÷ (mortgage payment factor + tax+insurance rate), then home price = loan + down payment. This is an estimate for planning, not a lender's underwriting calculation.

How much house can you afford based on your salary?

The table below holds monthly debts at $500, down payment at $50,000, rate at 6.5%, and a 30-year term, and only changes income, to show how the binding constraint shifts. At lower incomes, a fixed $500 of debt eats a bigger share of the 36% allowance, so the back-end limit binds. Once income is high enough that 36% of it, minus $500, exceeds 28% of it, the front-end limit takes over and debt stops mattering to the ceiling entirely.

Computed with the same formula as the calculator above.

How does a down payment change how much house you can afford?

A bigger down payment raises your max home price, but not dollar for dollar, because a pricier home also carries a bigger property-tax-and-insurance bill, and that bill competes for the same fixed monthly housing budget as the loan payment does. Holding income at $90,000, debts at $500, rate at 6.5%, and the tax+insurance estimate at 1.5%: with no down payment at all, the max home price is $277,386. At $50,000 down, it rises to $319,130, an increase of about $42,000 in price for $50,000 in cash. At $120,000 down, the max price reaches $377,573, an increase of $100,000 in price for $120,000 in cash. Every extra dollar of down payment buys slightly less than a dollar of extra home price, because part of the monthly budget that a larger loan would have used gets redirected to the larger tax and insurance bill a pricier home carries.

How does existing debt change how much house you can afford?

Existing debt only starts to hurt your max home price once it drags the 36% back-end limit below the 28% front-end limit. At $90,000 income with a $50,000 down payment, the front-end limit is a flat $2,100 a month. With $0, $300, or $500 in other monthly debts, the back-end limit ($2,200 or higher) still clears $2,100, so the front-end limit binds and the max home price stays at $319,130 in every case, debt or no debt. Only once other debts climb to $800 a month does the back-end limit drop to $1,900, undercutting the front-end limit and pulling the max home price down to $292,713. At $1,200 in other monthly debts, the max home price falls further to $239,877. The practical takeaway: a modest car payment or student loan bill may not touch your borrowing power at all if your income is high enough that the front-end limit was always the tighter constraint; a large one can cut tens of thousands off what you qualify for.

Is the maximum you can borrow the same as what you should spend?

No. The 28/36 rule tells a lender the largest payment it is willing to underwrite, not what is comfortable for your actual life. It does not know about your childcare costs, how much you want to save for retirement, whether your income is stable or commission-based, or what a maintenance fund for an older house should look like. Two households at the same income and debt level can have very different amounts of real slack in their budget. Borrowing right up to the 28% or 36% ceiling leaves little room for a bad year, and it assumes your other spending stays fixed while your housing payment claims its maximum share. Treat the calculator's output as the top of a range to consider, not a target to hit.

What role does mortgage rate and loan term play?

The interest rate and loan term do not change your max monthly housing payment (that is fixed by your income and debts), but they change how much loan that same monthly payment can support. A higher rate means more of each payment goes to interest, so less loan fits under the same payment ceiling; a longer term (30 years instead of 15) spreads the principal over more payments, lowering each one and letting a bigger loan fit under the same ceiling, at the cost of paying far more interest over the life of the loan. Freddie Mac's Primary Mortgage Market Survey, the standard reference for average U.S. mortgage rates, put the 30-year fixed rate at roughly 6.65% to 6.69% through August 2026; the calculator's 6.5% default sits close to that range, but you should use your own quoted rate for an accurate number.

The flat truth: a lender's maximum is not your budget

The 28/36 rule answers one narrow question: how big a payment will a lender's underwriting typically approve. It is a useful ceiling, and it explains why your pre-approval letter says what it says, but it was never built to answer whether that payment leaves you comfortable. Run the calculator with your own numbers to see the ceiling, then decide for yourself how far below it you actually want to spend, factoring in your own savings goals, your job stability, and the maintenance costs that come with owning instead of renting.

Related calculators: see the homeownership hub for the full picture of what a house costs beyond the sticker price, run the mortgage calculator for a full payment breakdown and amortization schedule once you have a price in mind, and check what credit score you need for a mortgage since your rate, and therefore your borrowing power, depends heavily on it.