Mortgage Affordability Calculator 2026
Find the maximum home price you can afford based on income, existing debts, and down payment. See your DTI and front-end ratios.
Lenders use the 28/36 rule: housing costs should not exceed 28% of gross monthly income, and total debt payments should not exceed 36% (DTI ratio). With $8,000 gross monthly income, maximum housing payment is $2,240 and total debts $2,880. FHA loans allow up to 43% DTI with compensating factors.
The 28/36 Rule Explained
Lenders use two DTI ratios to assess mortgage affordability:
- Front-end ratio (28%): Monthly housing costs (PITI) ÷ gross monthly income. Should not exceed 28%.
- Back-end ratio (36%): Total monthly debt payments (housing + all other debts) ÷ gross monthly income. Should not exceed 36%.
- Payroll Taxes Guide
- Overtime Rules
- Tax Withholding Guide
The lower of the two binding limits determines your maximum monthly housing payment. Then, working backward through the mortgage formula, you arrive at the maximum purchase price.
FHA vs Conventional Limits
Conventional loans: typically 28/36, flexible to 45–50% with strong credit. FHA loans: up to 31/43%, flexible to 50% with compensating factors. VA and USDA loans focus primarily on residual income rather than DTI ratios.