Debt-to-Income Ratio Calculator
Calculate your DTI ratio — the number lenders use to decide how much you can borrow.
Content updated August 10, 2026
Within Fannie Mae's maximum for manually underwritten loans.
Benchmarks are Fannie Mae Selling Guide maximums: 36% manually, up to 45% with credit-score and reserve requirements met, and up to 50% through Desktop Underwriter. Individual lenders set their own limits, so this is context rather than an approval decision.
Your debt-to-income ratio (DTI) is one of the first things a lender checks. It compares your total monthly debt payments to your gross monthly income, showing how much of your earnings are already committed. This calculator works out both the back-end ratio lenders weigh most heavily and the front-end housing-only ratio.
It also places your result against published Fannie Mae maximums so you can see where you sit. Those are benchmarks for context rather than an approval decision — every lender sets its own limits, and clearing one is not the same as the payment being comfortable.
The Debt-to-Income Ratio formula
DTI = (Total monthly debt payments ÷ Gross monthly income) × 100Total monthly debt payments = rent or mortgage, car loans, student loans, minimum credit-card payments and other loan repayments · Gross monthly income = your total income before tax. The result is a percentage.
Worked example
With $2,000 of monthly debt payments — say a $1,200 mortgage, $400 car loan and $400 in card minimums — on $6,000 gross monthly income, DTI = (2,000 ÷ 6,000) × 100 ≈ 33.3%, displayed as 33.3%. That sits under Fannie Mae's 36% manual-underwriting maximum.
Assumptions, rounding, and limitations
Assumptions
- Income is gross monthly income before tax and other deductions, matching the CFPB's definition.
- Debt payments are recurring contractual monthly obligations — housing, car loans, student loans, minimum credit-card payments and other loan repayments. Everyday spending such as groceries, utilities and subscriptions is not included.
- The result is a back-end ratio: housing is counted inside total debt rather than measured separately.
Rounding: The ratio is computed at full floating-point precision and displayed to one decimal place. The lender-view band is derived from the unrounded value.
Limitations
- Lender DTI limits vary by product, investor and individual overlay; this tool applies general published benchmarks and cannot tell you whether a specific lender will approve you.
- It does not verify how a lender will treat a particular obligation. Underwriters apply their own rules to items such as deferred student loans, co-signed debts, self-employment income and non-installment accounts.
- Clearing a DTI threshold is not the same as affordability. Because the ratio uses pre-tax income, a passing DTI can still consume a large share of take-home pay.
- This is general information, not lending, financial or legal advice.
Sources
- What is a debt-to-income ratio? — Consumer Financial Protection Bureau
- Qualified Mortgage Definition under the Truth in Lending Act (Regulation Z): General QM Loan Definition — Consumer Financial Protection Bureau
- Selling Guide B3-6-02: Debt-to-Income Ratios — Fannie Mae
What counts as a good DTI?
There is no single regulatory number. The CFPB states plainly that different loan products and different lenders apply different DTI limits, so the honest answer is that your target depends on the program you are applying to.
For a concrete published benchmark, Fannie Mae's Selling Guide sets a maximum total DTI of 36% for manually underwritten loans, which may be exceeded up to 45% when the borrower meets the credit-score and reserve requirements in the Eligibility Matrix. Loan casefiles underwritten through Desktop Underwriter allow up to 50%.
Treat 36% as a comfortable planning target rather than a pass/fail line, and remember that clearing a lender's maximum is not the same as the payment being affordable for your household.
Why 43% is no longer the rule it used to be
For years the figure quoted everywhere was 43%, because the General Qualified Mortgage definition under Regulation Z included a hard 43% DTI limit. That is no longer the test. The CFPB's General QM Final Rule removed the 43% DTI limit and replaced it with price-based thresholds: a loan meets the General QM definition when its annual percentage rate exceeds the average prime offer rate for a comparable transaction by less than 2.25 percentage points, with higher thresholds for smaller loan amounts, certain manufactured-housing loans, and subordinate liens.
The rule took effect on 1 March 2021 and its mandatory compliance date was extended to 1 October 2022. You will still see 43% cited widely, and individual lenders and investors are free to keep it as their own overlay, but it is a lender policy rather than the current General QM requirement.
This matters when you are shopping: because the current test is priced-based, a strong rate quote can carry a DTI that an older 43% rule of thumb would have told you was disqualifying.
Front-end and back-end ratios
The front-end ratio counts only housing costs against gross income. The back-end ratio counts every monthly debt payment including housing. Lenders generally weigh the back-end figure most heavily, and it is the number this calculator reports.
Enter the housing payment you will actually have. If you are applying for a mortgage, that means the proposed new payment rather than your current rent, since the new obligation is what the lender underwrites.
Frequently asked questions
▶How do I calculate my debt-to-income ratio?
Add up your monthly debt payments, divide by your gross (pre-tax) monthly income, and multiply by 100. This calculator does it for you and rates the result.
▶How can I lower my DTI?
Pay down existing debts (especially cards), avoid taking on new loans before applying for credit, or increase your income. Even small reductions can move you into a better lending bracket.
▶What is a good debt-to-income ratio?
There is no universal threshold — the CFPB notes that limits vary by loan product and lender. As a published benchmark, Fannie Mae allows 36% on manually underwritten loans, up to 45% with sufficient credit score and reserves, and up to 50% through Desktop Underwriter. Lower is still safer and generally cheaper.
▶Is 43% still the maximum DTI for a qualified mortgage?
No. The CFPB's General QM Final Rule removed the 43% DTI limit and replaced it with price-based thresholds tied to how far the loan's APR sits above the average prime offer rate. The rule became effective in March 2021 with a mandatory compliance date of 1 October 2022. Many lenders still apply 43% as their own overlay, so you may be quoted it as a limit — but it is lender policy, not the current General QM test.
▶What's the difference between front-end and back-end DTI?
The front-end ratio counts only housing costs against your income; the back-end ratio counts all your monthly debt payments, housing included. Lenders look most closely at the back-end figure.
▶Does rent count towards my DTI?
Yes — rent is a recurring housing payment, so lenders typically include it (or the proposed new mortgage payment). Everyday spending like groceries, utilities and subscriptions is not counted.
▶Is DTI based on gross or net income?
Gross income — your pay before tax and deductions. That's why your DTI can look lower than the share of your take-home pay that debts actually consume, so leave yourself a comfortable margin.
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Open calculator →Disclaimer: Debt-to-Income Ratio Calculator results are estimates for general information and education only, and are not financial, tax, legal or medical advice. Verify important decisions with a qualified professional.