What debt-to-income ratio do lenders allow?
It depends on the loan program, and lenders can set stricter limits of their own. For a Fannie Mae conventional loan, the maximum total debt-to-income ratio is 36% of stable monthly income when the loan is underwritten by hand, and it can go up to 45% if the borrower meets the credit score and reserve requirements. For loans run through Fannie Mae’s automated underwriting system, the maximum is 50% (Fannie Mae Selling Guide, B3-6-02).
Your total includes the new housing payment, property taxes and insurance included, plus your other monthly debts. That is why the same income buys a different price in a town with a higher property tax rate.
How much does property tax change what I can afford in Hays County?
A lot, because tax is part of the payment that gets measured against your income. For the 2026 tax year, combined rates across the towns I serve run from 1.42% in Wimberley to 2.12% in Austin, with Kyle at 2.10%, Buda at 1.94%, San Marcos at 1.95%, Dripping Springs at 1.73% and Driftwood at 1.51%.
On the same $400,000 price, that range is about $5,700 to $8,500 a year in tax before exemptions. Pick your town in the calculator and the real rate is built in. The full table, with a source for every rate, is on my Hays County page.
Debt-to-income is the real gatekeeper, not your income alone
Lenders do not just look at what you make. They look at what you make against what you already owe, all of it added together against your gross monthly income. That ratio, not your salary by itself, is usually what actually caps how much house you can buy.
Two people earning the same income can qualify for very different loan amounts depending on what else shows up on their credit report. A car payment or student loan you barely notice month to month can meaningfully change this number.
Self-employed or paid on 1099? Count your income the way a lender will
On a standard loan, a lender usually uses your income after business write offs, averaged over the last two years of tax returns. If you write off a lot, the number on your tax return can sit well below what actually lands in your accounts, and that smaller number is what this math sees.
Bank statement programs work differently. They qualify you on your deposits over 12 or 24 months instead, so your affordable price can come out higher. Run this calculator once with your tax return income and once with the income your deposits support, and I will show you which loan type fits where.
This is a ceiling, not a target
The number this calculator gives you is the top of what the math allows, not what I would necessarily recommend you spend. Plenty of buyers qualify for more than they actually want their payment to be, and that is a completely reasonable place to land.
I would rather show you the real ceiling and let you decide how close to it you want to live, than quietly assume you want to max it out.
Your down payment changes the ceiling more than people expect
A larger down payment does two things at once. It lowers your loan amount, which lowers your payment, and it can improve your pricing depending on the loan type. Both of those push your affordable price up, sometimes by more than people assume from a percentage point or two of difference.
This is also where down payment assistance programs can change the math entirely for a first-time buyer. If your savings are the limiting factor rather than your income, that is worth a real conversation before you assume a number is out of reach.
How much loan can I qualify for based on my income?
Your income sets the ceiling, but it is not the only number. A lender takes your gross monthly income, adds up your monthly debts plus the new housing payment, and checks that total against a debt-to-income limit for the loan program. Higher income with heavy debts can qualify for less than a moderate income with almost no debt.
Credit, down payment, and the loan type then move that ceiling up or down. Use the calculator above to see your ceiling on your own numbers, then a pre-approval confirms it with your real documents.
Is this a mortgage approval calculator?
It is an estimate, not an approval. People search for a mortgage approval calculator, a loan qualification calculator, or a what can I afford calculator, and they all mean the same thing: a quick way to see what the math allows. An approval is a lender decision based on your documents, your credit, and the property.
Treat the result as the number to start the conversation with. I will run the real version with you, and nothing on this page pulls your credit.
How much house can I afford with a lower credit score?
Credit score does not change the debt-to-income math, but it changes which loan programs you can use and how a loan is priced. Some programs are built for lower scores and higher debt, and others reward strong credit with better pricing. The same income can support a different price depending on the program that fits.
If your score is the sticking point, tell me where it is and I will show you which programs are realistic now, and what improving it would change, before you start shopping.
Getting pre-approved is a different, more precise step
This tool works off a target debt-to-income ceiling you set yourself. An actual pre-approval runs your real credit, your real income documentation, and the specific guidelines of the loan program that fits your situation, which can move this number in either direction.
Think of this as the conversation starter, the number that tells you roughly where to start looking, before we run the real one together.