Debt-to-Income Calculator Formula & How It Works
- Monthly debt = mortgage/rent + car + student + credit card minimum payments
- Gross income = pre-tax monthly income
- Front-end DTI: housing payment only ÷ income
- Back-end DTI: all debt ÷ income (what lenders primarily use)
DTI measures how much of your gross income goes to debt. Lenders use back-end DTI (all debts) to assess repayment ability. A DTI below 36% is generally considered good; many conventional mortgages allow up to 43–50% DTI with compensating factors.