Home Affordability Calculator
Estimate how expensive a house you can afford from your income, debts and down payment.
Results update as you type.
About this calculator
A home affordability calculator estimates the house price you can comfortably buy based on your income, existing monthly debts and down payment. It applies the standard lender debt-to-income limits — a front-end housing ratio and a back-end total-debt ratio — to find your maximum monthly payment, then works backward through the mortgage formula to a loan amount and a home price.
The two limits are the well-known 28/36 rule: housing should stay under 28% of gross monthly income, and all debt including housing under 36%. The tool takes the lower resulting payment. For example, on an 80,000 salary with 500 of other monthly debts, the back-end limit allows 1,900 for housing; after setting aside roughly 425 for property tax and insurance, about 1,442 covers principal and interest, which at 7% over 30 years supports a loan near 217,000 — so with 40,000 down, a home around 257,000.
Use it as a starting point for house-hunting and to see how a bigger down payment, a lower rate or paying off a car loan changes your budget. It estimates the loan you can carry, not a guaranteed approval; lenders also weigh credit score, employment and reserves, so treat the figure as an upper bound.
Frequently asked questions
What are the 28/36 rules?
A common lender guideline: spend no more than 28% of gross monthly income on housing (the front-end ratio) and no more than 36% on all debt including housing (the back-end ratio). This tool takes the lower of the two limits.
Does this include property tax and insurance?
No — it estimates the loan principal and interest you can carry. Real affordability is a little lower once property tax, home insurance and any HOA fees are added, so treat the figure as an upper bound.
How much house can I afford on my salary?
A rough guide is 3 to 5 times your gross annual income, but the real limit comes from the monthly payment your income and debts support at current rates. Enter your numbers above; a higher interest rate sharply lowers the price you can afford for the same monthly budget.
Does a bigger down payment let me afford more house?
Yes, twice over. The down payment adds directly to the price you can buy, and getting to 20% removes mortgage insurance, freeing more of your monthly budget for principal and interest. It also lowers the loan, reducing lifetime interest.
Why does paying off other debt increase what I can afford?
Because the back-end 36% limit counts all your debt. Every dollar of car or card payment you clear frees a dollar of the monthly budget for housing, which can add tens of thousands to the home price you qualify for.
What costs beyond principal and interest should I plan for?
Property tax, homeowners insurance, any HOA dues and mortgage insurance all ride on top of principal and interest, plus upkeep and closing costs. The advanced fields let you enter tax, insurance and HOA so the affordable price reflects the full monthly cost, not just the loan.
API — use this calculator from code
Call this calculator as a free JSON endpoint — no key required. Send the field values below as query parameters or JSON. Read the full API docs →
Endpoint
GET https://calculator.free/api/v1/home-affordability/curl
curl "https://calculator.free/api/v1/home-affordability/?income=80000&debts=500&down=40000&rate=7&years=30"JavaScript fetch()
const r = await fetch(
"https://calculator.free/api/v1/home-affordability/?" + new URLSearchParams({
"income": "80000",
"debts": "500",
"down": "40000",
"rate": "7",
"years": "30"
}));
const data = await r.json();
console.log(data.results);Results are estimates for general guidance only, not financial, medical or tax advice.