Debt-to-Income (DTI) Calculator

The front-end ratio counts housing alone: mortgage principal and interest, property taxes, homeowner insurance, mortgage insurance, and HOA dues if you pay them. The back-end ratio adds every other recurring debt, so car loans, student loans, credit card minimums, personal loans, and court-ordered support all land in it. The calculator defaults show how far apart the two can sit. On $8,000 of monthly income, a $2,000 housing payment is a 25 percent front-end ratio. Add a $450 car payment, $300 in student loans, and $150 in card minimums, and total debt reaches $2,900, a back-end ratio of 36.25 percent. The same income supports two different readings depending on which debts count, and lenders ask for both because each catches a different kind of overextension.

Which ceiling applies depends on the loan you want. Conventional mortgages backed by Fannie Mae and Freddie Mac use 43 percent back-end as the standard and go to 50 percent when the rest of the file is strong. FHA is the most forgiving on paper, reaching the mid 50s under manual underwriting with compensating factors. The VA program publishes 41 percent as a guideline and leans on a residual income test instead of a hard cap. Auto and personal lenders write their own rules, and most prefer applicants under 40 percent.

Take a borrower who earns $6,500 a month before taxes and wants a conventional mortgage. Her existing debts: a $380 car payment, $220 in student loans, and $95 in credit card minimums, $695 in all. At the 43 percent back-end cap she can carry $2,795 in total monthly debt (6,500 x 0.43). Subtract the $695 she already owes and $2,100 remains for the full mortgage payment, taxes and insurance included. The front-end guideline tightens that. At 28 percent, housing alone should stay under $1,820. A $2,050 payment would pass the back-end test at 42.2 percent while pushing the front-end ratio to 31.5 percent. Many lenders will approve that anyway, since the back-end number carries more weight, but the file sits close enough to the line that any surprise on the appraisal or the rate could tip it. Now suppose she pays off the car before applying. Her other debts drop to $315, and the same $2,050 payment puts her back-end ratio at 36.4 percent, comfortably inside every program. One cleared loan moved her from the edge of approval to an easy file without a single extra dollar of income.

DTI says nothing about what is left over. A single borrower earning $15,000 a month at 43 percent DTI still has $8,550 after debts; a family of five earning $5,000 at the same ratio has $2,850 before food, childcare, and utilities. The ratio scores them identically. VA underwriting is the one program that corrects for this, pairing its DTI guideline with a residual income table that varies by family size and region. For your own planning, a payment that satisfies the lender can still be more house than your budget wants, so run the numbers against actual take-home pay before you commit.

Erasing an entire payment beats shrinking balances. A $400 car payment that disappears removes the full $400 from the numerator the day the account closes, while a year of extra principal on that same loan changes nothing until it is gone. Credit cards are the exception because lenders count the statement minimum: cutting a $5,000 balance to $1,000 can drop the counted payment from about $150 to $25. The denominator moves too. A documented raise, a second job with some history behind it, or bonus income averaged over two years all enlarge it. In the months before a mortgage application, avoid financing anything new, since a fresh $500 payment shrinks your housing budget by exactly $500. The CFPB's home buying resources cover the timing of these moves alongside the rest of mortgage preparation.