What is a house affordability calculator?

A house affordability calculator is a free online tool that helps you calculate the maximum home price you can afford from income, debts, down payment, and rate. Limited by front-end DTI (housing < 28% of income) and back-end DTI (total debt < 36-43% of income). It runs entirely in your browser with instant results and no sign-up.

Is this a substitute for a lender's pre-approval?

No — actual loan terms depend on credit, income docs, and lender underwriting. Use this for planning and what-if scenarios; get a real Loan Estimate before making decisions.

Do calculations include taxes and insurance?

When the calculator asks for them. PITI calculations include property tax, insurance, and PMI; raw P&I calculations don't.

Why does my actual payment differ?

Lenders round payment amounts and may include escrow buffers. Property tax and insurance change over time. Real payments vary 1-5% from these estimates.

Free house affordability calculator

How it's calculated

How the house affordability works

Limited by front-end DTI (housing < 28% of income) and back-end DTI (total debt < 36-43% of income).

max housing = income × 28%

max debt = income × 36% − other debts

max P&I = max housing − tax − ins − HOA

Source: standard mortgage / personal finance formulas.

Accuracy

How accurate is this house affordability?

Every formula on this site comes from an established, published source for its field — standard references in mathematics, finance, health, and engineering, not invented in-house. The math is implemented as a pure TypeScript function and tested against published reference values before going live. See the Methodology page for the full sourcing process.

Results are mathematically correct for the inputs provided. They are estimates only— real-world outcomes depend on factors specific to your situation, such as fees, taxes, timing, local rules, and assumptions that can change after the calculation date. See the Disclaimer for the limits on what to rely on a result for.

These pair naturally with this one for decisions that sit nearby.

Questions

Frequently asked questions about the free house affordability calculator

What is a house affordability calculator?
A house affordability calculator is a free online tool that helps you calculate the maximum home price you can afford from income, debts, down payment, and rate. Limited by front-end DTI (housing < 28% of income) and back-end DTI (total debt < 36-43% of income). It runs entirely in your browser with instant results and no sign-up.
Is this a substitute for a lender's pre-approval?
No — actual loan terms depend on credit, income docs, and lender underwriting. Use this for planning and what-if scenarios; get a real Loan Estimate before making decisions.
Do calculations include taxes and insurance?
When the calculator asks for them. PITI calculations include property tax, insurance, and PMI; raw P&I calculations don't.
Why does my actual payment differ?
Lenders round payment amounts and may include escrow buffers. Property tax and insurance change over time. Real payments vary 1-5% from these estimates.