Learn · debt-to-income
Debt-to-income ratio (DTI), explained, with a calculator
Lenders compare your monthly debts with your income. Here’s how it works, what counts, and a calculator that shows what changes when you pay a debt off.
What DTI is
Your debt-to-income ratio is your monthly debt payments divided by your gross (before-tax) monthly income. The CFPB’s example: $2,000 a month in debts and $6,000 a month in income is a 33% DTI.
Front-end vs back-end
- Front-end (housing ratio): the new monthly housing payment (principal, interest, taxes, insurance and HOA dues) divided by gross monthly income.
- Back-end (total): the housing payment plus all other monthly debts, divided by gross monthly income. This is the one most guidelines focus on.
What usually counts
- The new housing payment, including HOA or condo dues
- Car loans, student loans and other installment debts with more than 10 months left
- Credit card minimum payments, even if you pay in full
- Car leases, however long is left
- Child support and alimony that continue more than 10 months
- Other mortgages, or a net loss on a rental
What usually doesn’t
- Utilities, phone and internet
- Groceries, gas and other living costs
- Car and health insurance premiums
- Subscriptions and memberships
- An installment loan with 10 or fewer payments left, unless it’s large enough to affect your ability to pay
Examples
- Income $6,500/month. New housing payment $2,000. Car $450, card minimums $90, student loan $160. Front-end 30.8%; back-end 41.5%.
- Same buyer pays off the car before closing: back-end drops to 34.6%.
- A car with 8 payments left may not count, but lenders can still count it if the payment is large. Ask before you pay anything off.
How lenders look at it (generally)
- Fannie Mae (conventional): for manually underwritten loans, a 36% maximum total DTI, up to 45% with the credit score and reserves in Fannie Mae’s Eligibility Matrix. Loans run through Desktop Underwriter (DU) can go up to 50%. (Selling Guide B3-6-02)
- FHA: for manually underwritten loans, 31% housing and 43% total with no compensating factors; up to 37/47 with one, or 40/50 with two, for scores of 580 and up. Scores of 500–579 stay at 31/43. FHA loans can also be approved through FHA’s automated TOTAL Mortgage Scorecard. (HUD Handbook 4000.1; Mortgagee Letter 2014-02)
- Every lender and program is different, and DTI is only one part of the decision. These figures are not an approval limit for you.
DTI calculator
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Not sure? Estimate it with Can I afford it?
Front-end (housing)
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Back-end (total)
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Back-end if ticked debts are paid off
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Reference points from the guides above: 36%, 43%, 45% and 50%. They’re not approval limits for you; the lender’s review decides.
Last checked October 17, 2026. Sources: CFPB, What is a debt-to-income ratio? · Fannie Mae Selling Guide B3-6-02, debt-to-income ratios · HUD Handbook 4000.1, FHA Single Family Housing Policy · HUD Mortgagee Letter 2014-02, FHA manual underwriting ratios
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