Debt-to-income ratio is the share of your gross monthly income that goes to debt payments. Lenders look at two versions: the front-end ratio counts only the housing payment, and the back-end ratio counts housing plus every other monthly debt. Both are calculated before taxes, on gross income rather than take-home pay.
Debt-to-Income (DTI) Ratio Calculator
Lenders use two debt-to-income ratios to decide what you qualify for: the front-end ratio (housing only) and the back-end ratio (all your debt). Enter your income, current debts, and the housing payment you are considering to see both.
Your numbers
Your ratios
Monthly debts means car loans, student loans, credit-card minimums, and personal loans, not rent, utilities, or groceries. Conventional loans usually want back-end DTI at or under 43–45%; FHA can go to about 50% with compensating factors. This is guidance, not a preapproval.
Related free tools: how much house can I afford · house hacking calculator · down payment roadmap
What is a debt-to-income ratio?
The calculation is a fraction. The top is what you owe every month, and the bottom is your gross monthly income, meaning income before taxes and deductions. The front-end ratio puts only the proposed housing payment on top: principal, interest, property taxes, insurance, mortgage insurance, and any HOA dues. The back-end ratio adds car loans, student loans, minimum credit card payments, personal loans, and court-ordered payments such as child support.
Costs that are not debt stay out of it. Groceries, utilities, phone bills, insurance premiums other than the ones bundled into the housing payment, and retirement contributions do not appear, which is why a ratio a lender considers comfortable can still feel tight once the actual bills arrive.
What debt-to-income ratio do you need for a mortgage?
There is no single number, because each loan program sets its own. FHA's Single Family Housing Policy Handbook treats 31% front-end and 43% back-end as the permissible ratios, and requires the lender to document compensating factors when either is exceeded. Fannie Mae's Selling Guide caps manually underwritten loans at 36% total, allows up to 45% when the borrower meets credit score and reserve requirements, and allows up to 50% for loans run through Desktop Underwriter.
Those are ceilings set by the program, not by the lender you talk to. Individual lenders apply overlays that are stricter, so an approval at the top of a program's range is not something to count on when you are planning.
Debt-to-income limits by loan program
The same ratio gets a different answer depending on which program you use, and the four you are most likely to meet are not built the same way. This table is the manual-underwriting benchmark for each; automated approvals often go higher, and lender overlays often go lower.
| Program | Front-end | Back-end | What moves it |
|---|---|---|---|
| FHA | 31% | 43% | Documented compensating factors; TOTAL Scorecard approvals commonly run higher |
| Conventional (Fannie Mae) | none set | 36%, 45% with credit and reserves, 50% through Desktop Underwriter | Credit score and reserves |
| VA | none set | 41% benchmark, no hard cap | Residual income: above 41% is approvable when residual income beats the VA table by 20% or more, otherwise a supervisor signs off |
| USDA guaranteed | 29% | 41% | Waiver to 32% and 44% with a 680+ score and one compensating factor; GUS Accept files need no waiver |
VA is the odd one out and the one most often misread. It is a residual-income program first, so a veteran at 45% back-end with strong residual income can be a cleaner file than a civilian at 40% with none.
If you are using VA entitlement on a two-to-four unit property, the VA duplex and fourplex guide walks through how the rental side is counted. For the FHA-versus-conventional choice on a house hack, this comparison runs the numbers side by side.
Self-employed or variable income: how lenders count it
The calculator takes whatever annual income you type, but a lender will not. Self-employment income is qualified from your signed federal tax returns, and Fannie Mae's Selling Guide asks for a two-year history of it, with a narrower path for a borrower whose most recent returns show a full twelve months from the current business.
The number the underwriter uses is the income the returns support after business expenses, typically averaged across the two most recent years, and a declining trend has to be explained rather than averaged away.
Bonus, overtime and commission income follow the same logic: a history of receipt, usually two years, before it counts. So if your take-home is strong but your Schedule C is thin, run this calculator twice, once with the income you actually earn and once with the income your returns show, and treat the second number as the one a lender sees.
How to lower your debt-to-income ratio before applying
Two levers move the number and they move it at different speeds. Paying off a small installment loan removes its whole payment from the ratio immediately, which is why retiring a car loan with a few payments left often does more than paying down a much larger balance elsewhere. Raising documented income works too, though lenders generally want a history behind new income rather than a recent raise alone.
One lever to use with care is moving debt around. Consolidating balances onto a new card or a personal loan can lower your DTI when it lowers the required monthly payment, because DTI counts the payments a lender must count, not the balance itself. The gain is not automatic: the lender has to verify the old debts are paid off, opening new credit shortly before applying can set you back, and the total interest you pay can rise.
How debt-to-income ratio interacts with house hacking
Rental income from a property you are buying can sometimes be counted toward qualifying income, which changes the arithmetic for a duplex or triplex where you live in one unit. Programs differ on how much of the projected rent counts and what documentation they require, so treat it as a question for the loan officer rather than an assumption.
Once you know the payment you can support, the affordability calculator turns it into a price range, and the house hacking calculator shows what a duplex would actually cost you to live in each month.
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Sources
FHA qualifying ratios: HUD, FHA Single Family Housing Policy Handbook 4000.1. Conventional loan limits: Fannie Mae Selling Guide B3-6-02, Debt-to-Income Ratios. Both re-checked on 28 July 2026. VA ratio and residual-income rules: 38 CFR 36.4340, VA underwriting standards (the 41% ratio) and VA Lenders Handbook Pamphlet 26-7, Chapter 4. USDA ratios and waivers: RD Handbook HB-1-3555, Chapter 11. Self-employment income: Fannie Mae Selling Guide B3-3.2-01. These three checked on 15 September 2026.
Frequently asked questions
What is a good debt-to-income ratio to buy a house?
A good ratio is defined as one comfortably below the program ceiling rather than at it. FHA treats 31% housing and 43% total as its permissible ratios and Fannie Mae allows up to 50% through Desktop Underwriter, but a borrower approved near those limits has little room for a rate change, a repair, or a month of reduced income.
Does debt-to-income use gross or net income?
Debt-to-income uses gross income, defined as total earnings before taxes, insurance premiums, and retirement contributions are deducted. This is why a ratio that looks acceptable on paper can consume a much larger share of the money that actually reaches your bank account.
Do utilities and groceries count in debt-to-income ratio?
They do not. The ratio counts debt obligations, defined as recurring payments on borrowed money plus the proposed housing payment, so utilities, groceries, phone bills, childcare, and insurance premiums outside the housing payment are excluded. Budgeting for them is on you, not on the underwriter.
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