What Is the Home Affordability Calculator?
A home affordability calculator answers the question every buyer asks: how much house can I afford? Using your income, existing debts, down payment, and expected rate, it applies the widely used 28/36 mortgage rule to suggest a maximum monthly payment and home price.
How to use this calculator
Type your numbers into the fields above. The results change the moment you edit any input, so you can try one scenario after another and see exactly what moves. Most calculators show a short summary of the key figures, a line-by-line breakdown underneath, and — where it applies — a year-by-year schedule you can export to a spreadsheet. Everything runs in your browser; nothing is stored or sent anywhere. Treat the output as a planning estimate, not as final word on a real decision.
The Formula
Lenders generally cap housing costs at 28% of gross monthly income and total debt payments at 36%. The calculator takes the lower of those two limits, subtracts estimated taxes and insurance, and backs out the largest loan that fits — then adds your down payment to estimate the maximum home price.
Worked Example
With $90,000 of income ($7,500/month), 28% is $2,100 and 36% less $400 of other debt is $2,300, so the housing cap is $2,100. After subtracting $420 of tax and insurance, about $1,680 is available for principal and interest. At 6.5% over 30 years that supports a loan near $254,000; with a $60,000 down payment, a home price around $314,000.
Tips for the Most Accurate Estimate
- Use your full gross income, including bonuses only if they are reliable.
- Include all monthly debts — cards, loans, alimony — not just the mortgage.
- A bigger down payment directly raises the home price you can afford.
- Remember taxes, insurance, and possibly HOA dues sit on top of the mortgage.
- Stress-test the payment against a rate 1% higher before committing.
Frequently Asked Questions
Q: What is the 28/36 rule?
It is a lending guideline that keeps housing costs at or below 28% of gross income and total debt at or below 36%. Lenders use it to gauge whether you can comfortably afford a mortgage.
Q: Is the result a guarantee I will be approved?
No. It is a planning estimate. Lenders also review credit score, job history, and program-specific limits before approving a loan.
Q: Why does my down payment matter so much?
A larger down payment reduces the loan you need, lowers the monthly payment, and can help you avoid mortgage insurance.