Debt-to-Income Ratio Calculator

DTI is the share of your gross (pre-tax) monthly income that is committed to recurring debt payments. Lenders use it as a quick read on whether a new loan would stretch you too thin. The lower the ratio, the more cushion you have for living expenses, savings, and unexpected costs. A 25% DTI means a quarter of your gross income is going to fixed debt payments before taxes; a 45% DTI leaves very little room for anything else.

Front-end DTI looks only at your housing payment (mortgage principal, interest, property tax, insurance, plus HOA, or rent) divided by gross monthly income. Back-end DTI adds every other recurring debt: car loans, student loans, credit card minimums, personal loans, child support, and alimony. Mortgage underwriters look at both, but the back-end ratio is the one that usually decides approval, because it captures your full obligation load.

This calculator uses Fannie Mae context, not an approval decision. Its manual-underwriting guideline is 36%, specified manual exceptions can reach 45%, and Desktop Underwriter can allow up to 50% in eligible cases. FHA, VA, jumbo, and portfolio loans use different standards, and lenders consider credit, reserves, income documentation, and the full file. Ask the lender which program rules apply before treating a DTI result as an approval limit.

You only have two levers: shrink the numerator (monthly debt) or grow the denominator (gross income). The fastest wins on the debt side are paying off the smallest balances to eliminate their minimum payments, refinancing high-rate debt to a lower payment, and consolidating cards. On the income side, document side income, overtime, or bonuses that have a two-year history; lenders count it. Avoid taking on new debt in the 90 days before a mortgage application.

No. Credit score and DTI measure different things and lenders look at both. Your score reports how reliably you have paid past debt; DTI measures whether your current cash flow can absorb a new payment. A 780 score with a 48% back-end ratio still gets declined by most conventional underwriters because the income simply does not cover the debt load. Strong credit can earn a better rate, but it cannot push DTI under the program cap for you.