House Affordability Calculator
Adjust the inputs below. Results update as you type.
How it works
Lenders use two DTI ratios: front-end (PITI ≤ 28% of gross income) and back-end (all debt ≤ 36–43%). PITI = principal + interest + taxes + insurance. Enter income, monthly debts, down payment, and estimated property tax and insurance rates. Pre-qualification is an estimate; actual approval depends on credit score, employment history, and lender-specific overlays.
Input guidance
- Use sustainable gross income, not a one-time peak month.
- Include revolving and installment debts that appear on credit reports.
- Estimate taxes and insurance for the area you are shopping—not national averages alone.
The formula
Affordability is driven by debt-to-income limits: lenders typically cap total housing costs near 28% of gross monthly income and total debt near 36%. Maximum payment = income × limit − other debts; the price follows from that payment, rate, and term.
Worked example
On $7,000 gross monthly income, a 28% front-end limit allows about $1,960 for housing. After tax and insurance, that might support a loan around $250,000–$280,000 depending on the rate.
More examples to test
- $110,000 income, $600/month debts, 10% down: estimate max price under a 36% back-end DTI.
- Raise property-tax and insurance assumptions by 20% and re-check the affordable price.
How to interpret results
Treat the max price as a planning ceiling. Lenders still underwrite credit, employment, reserves, and property specifics.
When this can be inaccurate
DTI limits, PMI, HOA, and local tax rules vary by lender and market. Pre-approval can differ from this estimate.
Change history
- July 2026: Published with DTI planning notes and lender-overlay caveats.
Site-wide corrections also appear on the corrections log.
Get pre-qualified for a mortgage
Soft credit check — no impact to your score.
Frequently asked questions
What is the 28/36 rule?+
A common guideline: keep housing costs under 28% of gross income and all debt payments under 36%. Lenders use similar ratios to size loans.
Does the down payment change affordability?+
Yes. A larger down payment lowers the loan and monthly payment, and a 20% down payment avoids PMI, increasing what you can comfortably buy.
What costs count as housing?+
Principal, interest, property tax, homeowners insurance, and any HOA or PMI — lenders evaluate the full payment, not just principal and interest.
Is the affordable price the same as what I should buy?+
No. Affordability is a qualification-style ceiling. Your budget, reserves, and comfort with payment risk may call for a lower price.
Why do lender quotes differ from this estimate?+
Lenders apply overlays for credit score, reserves, employment history, and property type that a simple DTI model cannot fully capture.
Guided next steps
Want the full workflow? Use this calculator inside a step-by-step guide.
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