Real Estate Affordability Calculator

Real Estate Affordability Calculator

This calculator estimates the maximum home price you can afford based on your income, existing debts, down payment, and current mortgage rates. Use it before you start house hunting to set a realistic budget and avoid falling in love with a property that stretches your finances too thin.

How Home Affordability Is Calculated

Lenders use two debt-to-income (DTI) ratios to determine how much you can borrow:

• Front-end DTI (28% rule): Your monthly housing payment should not exceed 28% of gross monthly income
• Back-end DTI (36% rule): Total monthly debts (housing + car loans + student loans + credit cards) should stay below 36% of gross income
• Max Loan Amount is derived by solving the mortgage payment formula: Loan = Payment x [(1+r)^n - 1] / [r x (1+r)^n]
• Max Home Price = Max Loan + Down Payment

Example

Key Factors That Affect Affordability

• Interest rate — even a 0.5% rate change can shift your buying power by $20,000-$40,000
• Down payment size — 20% down avoids private mortgage insurance (PMI) and increases your price range
• Existing debt load — high monthly obligations reduce the mortgage payment a lender will approve
• Loan term — a 15-year mortgage has higher payments but saves significantly on interest
• Property taxes and insurance — these are not included in the base calculation but will affect your true monthly cost

Tips

1. Get pre-approved before shopping so you know your real ceiling, not just an estimate
2. Budget for closing costs (typically 2-5% of the purchase price) on top of your down payment
3. If your DTI is above 36%, focus on paying down debts before buying to unlock a higher price range
4. Compare 15-year versus 30-year terms in the calculator to see the tradeoff between payment size and total interest