Home Affordability Calculator — How Much House Can I Afford?

The 28/36 rule, in plain terms

Most lenders lean on two simple ratios to figure out what you can safely borrow. The first, called the front-end ratio, caps your total housing payment — principal, interest, taxes, insurance, the works — at roughly 28% of your gross monthly income. The second, the back-end ratio, caps everything you owe each month, housing included, at around 36% of that same gross income.

Here's the part that trips people up: this home affordability calculator checks both ratios and uses whichever one is lower. If you're carrying a car payment and a couple of student loans, the back-end ratio usually becomes the real ceiling — not the front-end one. The Consumer Financial Protection Bureau has a clear breakdown of how debt-to-income ratios work if you want the full picture.

Why your existing debts matter so much

Every dollar of monthly debt you're already paying is a dollar lenders assume you can't put toward housing. A $500 car payment doesn't just cost you $500 — it can shrink your affordable home price by $60,000-$80,000 or more, because that $500 eats directly into your 36% back-end ceiling.

This is why paying off a card or two before house hunting sometimes moves the needle more than saving a bigger down payment.

How your down payment shifts the number

Your down payment doesn't change your max monthly payment — it changes how big a home that payment can buy. More down means a smaller loan for the same monthly budget, which stretches your max home price higher. It also affects whether PMI eats into your housing budget at all, the same way it does on a standard mortgage calculator.

A real example, worked out

Take a $90,000 salary — $7,500 gross a month. The front-end cap is 28%, or about $2,100 for housing. With $400 in other monthly debts, the back-end cap works out higher in this case, so the front-end number of $2,100 is what actually limits things.

Feed that housing budget, a $30,000 down payment, a 6.6% rate and average tax and insurance figures into this home affordability calculator (or check exact figures with our mortgage calculator), and it lands on roughly $346,000 as an affordable home price. Change any number above and watch it recalculate instantly.

How to use this calculator

Start with your gross annual income — before taxes, not your take-home pay. Add up your real monthly debt payments: car loans, student loans, minimum credit card payments, anything that shows up on a credit report.

Enter what you've actually saved for a down payment, a realistic interest rate, and reasonable property tax and insurance estimates for your area. The calculator does the rest, checking both ratios and giving you the lower, more conservative figure.

Your ratio caps depend on the loan type

The 28/36 numbers this home affordability calculator uses are the conventional-loan standard, but they're not fixed across every loan program. FHA loans are generally more forgiving — lenders will often go up to a 43-50% back-end ratio with compensating factors like strong credit or cash reserves.

VA loans don't enforce a hard back-end cap at all, though most VA lenders still want to see something reasonable, typically under 41%. Conventional loans through Fannie Mae or Freddie Mac usually top out around 45%, sometimes 50% with an excellent credit profile.

None of this means you should stretch to the max a lender allows — it just means the "28/36" figure here is a sensible, conservative starting point, not a hard ceiling every lender enforces identically.

Common mistakes people make estimating what they can afford

The biggest one is anchoring on the maximum number instead of a comfortable one. Just because a lender will approve you at 43% back-end doesn't mean that payment leaves room for savings, emergencies, or simply breathing.

A second common mistake is forgetting maintenance and utilities — this calculator estimates your mortgage payment, not the full cost of owning a home, and older or larger homes especially can add hundreds a month beyond PITI.

The third is ignoring how a variable expense like property tax can climb after a purchase, particularly in areas where assessments reset to the sale price.

How much down payment do you actually need?

There's no universal answer, and the honest one depends on which trade-off matters more to you. Putting down less gets you into a home sooner, but it means a bigger loan, a bigger monthly payment, and PMI added on top until you build up 20% equity.

Conventional loans allow as little as 3% down for qualified first-time buyers. FHA loans go to 3.5%. VA loans, for eligible veterans and service members, can go to 0% down with no PMI at all — one of the more overlooked benefits of that program.

The trade-off with a smaller down payment isn't just PMI, though. It's also less room to negotiate, less cushion if the home needs repairs right after closing, and a bigger monthly number eating into your budget every single month for years.

A useful way to think about it: run this home affordability calculator twice, once with your actual savings and once with a larger hypothetical down payment. The gap between the two affordable price ranges tells you exactly what an extra $10,000 or $20,000 saved is worth to your buying power.

Why the same income affords different homes in different states

Two people earning identical $90,000 salaries, with identical debts and down payments, can end up with meaningfully different affordable price ranges depending on where they're buying — and it's not really about the mortgage rate. Property tax rates and home insurance costs vary enormously by state, and both eat directly into that 28% housing budget alongside principal and interest.

A buyer in a low property-tax state can typically afford a higher purchase price on the same income, simply because less of their monthly housing budget gets consumed by tax and insurance, leaving more room for principal and interest.

A buyer in a high property-tax or high-insurance state — think coastal areas prone to storms, or states with steep local tax rates — sees the opposite effect, even with an identical salary.

This is exactly why the tax rate and insurance fields in the calculator above matter as much as they do. Plugging in a rough national average instead of your actual local numbers can meaningfully overstate or understate what you can really afford, so it's worth a quick search for your specific county's property tax rate before you rely on the result.

What to do before you start house hunting

Run the numbers here first, but don't stop there. A few practical steps tend to save people real money and real stress once they're actually under contract.

Pull your credit report and check it for errors — a wrong late payment or an account that isn't actually yours can drag your score down and cost you a meaningfully worse rate. Pay down high-interest debt where you can, even modestly, since it directly loosens your back-end ratio and can raise your affordable price range without saving another cent.

Get pre-approved, not just pre-qualified, before you start seriously touring homes — and budget for the one-time expense with our closing cost calculator — a pre-approval carries real weight with sellers in a competitive market and forces you to have this exact affordability conversation with an actual lender rather than a calculator.

And build in a buffer: aiming a little under your calculated maximum, rather than right at it, gives you room for the moving costs, furniture, and inevitable first-year surprises that come with owning instead of renting.

Comparing your number to what you pay in rent

A useful sanity check once you have an affordable price range: compare the resulting monthly payment to what you're currently paying in rent. If your calculated housing budget is dramatically higher than your rent, that gap is worth sitting with for a moment rather than rushing past.

It doesn't necessarily mean you shouldn't buy — building equity instead of paying a landlord is still usually the stronger long-term move, and a mortgage payment is one of the few debts that can build wealth instead of just costing you money.

But if the jump feels uncomfortable on paper, it will feel uncomfortable in your actual bank account too, regardless of what a lender is willing to approve you for.

On the other hand, if your current rent is close to or above what this calculator says you can afford in home payments, that's often a sign you're already financially ready to buy, and the main thing standing between you and a purchase is simply the down payment and closing costs rather than ongoing affordability.

How your credit score changes what you can afford

This calculator asks for an interest rate, but it's worth understanding where that rate actually comes from, because your credit score has an outsized effect on it. Lenders price risk into your rate, and a lower score signals more risk to them, plain and simple.

The practical gap between a 620 credit score and a 760 credit score is often half a percentage point or more on your rate. On a $350,000 loan, that difference alone can mean $100 to $150 more or less every single month — money that either expands or shrinks your realistic price range before you've even touched your down payment or debts.

If your score has room to improve, even a few months of on-time payments and lower credit card balances before you apply can measurably change the rate a lender offers, which changes the home price this calculator will show you as affordable. It's often the single highest-leverage thing you can do in the months before buying, more impactful than most people expect.

Dual-income households and this calculator

When two incomes go toward qualifying, lenders combine both gross incomes and both sets of debts into a single household ratio, the same approach this calculator assumes if you enter combined figures.

What's worth watching is that combining incomes also combines debt — a partner with strong income but heavy existing debt can move the household ratio less favorably than expected, even though the total income figure looks larger on paper.

Running the numbers both individually and combined, the same way covered earlier for co-borrowers generally, helps clarify whether applying jointly genuinely helps your specific numbers or whether one applicant alone might actually qualify for more.

Why the same income affords different homes in different cities

Two households earning identical incomes can see meaningfully different affordable price ranges purely based on local property tax rates and insurance costs, both of which eat into the same 28% housing budget alongside principal and interest. A lower local tax rate leaves more room in that budget for the loan itself, which raises the affordable price range even with identical income.

This is exactly why plugging in your actual local tax rate and insurance estimate, rather than a generic national average, matters so much for getting a realistic number out of this calculator. A quick search for your target county's average property tax rate takes a few minutes and meaningfully improves accuracy.

The gap between "approved for" and "comfortable with"

This calculator, like a lender's own underwriting, shows what you could likely qualify to borrow based on standard ratios — not necessarily what you'd feel comfortable actually paying every month. Plenty of borrowers get approved at the maximum a lender allows and then find that number leaves uncomfortably little room for savings, emergencies, or simply everyday flexibility.

It's worth treating this calculator's output as a ceiling to be aware of, not a target to aim for by default. Many financial planners suggest budgeting a bit under the calculated maximum specifically to preserve that breathing room, even when a lender would approve a higher amount.

Does the time of year affect affordability?

Home prices and buyer competition shift seasonally in most markets, typically peaking in spring and summer and cooling in late fall and winter, which can indirectly affect what this calculator's price range actually gets you. The same affordable budget might stretch further during a slower season with less bidding competition, even though your income and debt-based ceiling hasn't changed at all.

This isn't something the calculator itself models, since it's about market timing rather than personal finances, but it's worth keeping in mind when interpreting your result — the dollar figure is fairly stable, but what that figure buys can vary meaningfully depending on when you're shopping.