What your result means
Front-end DTI uses only proposed housing expense. Back-end DTI adds the recurring monthly debts you entered and divides the total by gross monthly income.
Formula and assumptions
Front-end DTI = housing expense ÷ gross monthly income × 100. Back-end DTI = (housing expense + other monthly debts) ÷ gross monthly income × 100.
- Income is qualifying gross monthly income.
- Housing includes principal, interest, taxes, insurance, mortgage insurance, and HOA where applicable.
- Debt input follows the lender's definition of recurring obligations.
Worked example
$2,500 housing plus $1,000 other debts on $10,000 gross monthly income produces 25% front-end DTI and 35% back-end DTI.
Limitations
Lenders calculate income and obligations under product-specific rules. DTI alone does not determine approval, and a qualifying ratio can still be uncomfortable in a household budget.