Pre-tax monthly income from all sources.
Mortgage PITI (principal, interest, taxes, insurance) or current rent.
Auto loan monthly payment(s).
Monthly student loan minimum payments.
Minimum monthly payments on all credit cards.
Any other recurring debt: personal loans, alimony, child support, etc.
Back-End DTI
40.0%
All monthly debt payments ÷ gross income. Most lenders require ≤ 43%.
Front-End DTI
25.0%
Housing payment ÷ gross income. Most lenders prefer ≤ 28%.
Total Monthly Debt
$2,400
Sum of all recurring monthly debt payments.
Income After Debt Payments
$3,600
Gross monthly income remaining after all debt payments.
Estimate only — not financial advice; lender terms, fees, and taxes vary. Read the full disclaimer ↓
Each monthly obligation as a share of your gross income, plus your front-end and back-end DTI — the same ratios as the calculator above.
| Item | Monthly amount | % of gross income |
|---|---|---|
| Housing payment | $1,500 | 25.0% |
| Car payment | $400 | 6.7% |
| Student loans | $300 | 5.0% |
| Credit card minimums | $200 | 3.3% |
| Other debt | $0 | 0.0% |
| Total monthly debt (back-end DTI) | $2,400 | 40.0% |
| Housing only (front-end DTI) | $1,500 | 25.0% |
| Income after debt payments | $3,600 | 60.0% |
Front-end DTI (housing ratio) includes only the monthly housing payment (PITI for mortgages).
Gross monthly income of $6,000 with $1,500 mortgage, $400 car, $300 student loans, and $200 credit cards.
Gross Monthly Income
$6,000
Housing Payment
$1,500
Total Monthly Debt
$2,400
Front-End DTI
25.0%
Back-End DTI
40.0%
Income After Debt
$3,600
Front-end DTI of 25% and back-end of 40% — both under the conventional limits of 28%/43%. This borrower would qualify for most conventional mortgage programs.
Debt-to-income (DTI) compares your monthly debt payments to your monthly income, and lenders lean on it heavily when approving a mortgage or loan. There are two versions: the front-end ratio counts only your housing payment, while the back-end ratio counts all recurring debt — housing, car, student loans, credit-card minimums, and other instalments.
Knowing both before you apply removes the guesswork. The back-end ratio is usually the binding one, since it captures everything you owe each month, not just the roof over your head.
Two definitions trip people up. DTI uses gross (pre-tax) income, the convention lenders follow — using take-home pay will overstate your ratio. And only debt payments belong in the numerator: utilities, groceries, insurance, and subscriptions are expenses, not debts, and do not count.
For credit cards, use the minimum required payment rather than the full balance, and when applying for a mortgage, use the proposed new housing payment, not your current rent. Small definition errors can swing the ratio by several points.
Many conventional programs prefer a front-end ratio at or below 28% and a back-end ratio at or below 43%, though plenty of loans allow more. A back-end ratio comfortably under the limit signals room to borrow; one near or above it suggests paying down debt or raising income before you apply.
These are guideposts, not hard walls — the CFPB notes the ratio is a measure of your ability to manage monthly payments, and the exact cutoff depends on the loan program.
Because the ratio is driven by monthly payments, paying off a small, nearly finished instalment loan — a car loan with a few payments left — can drop your back-end DTI quickly by removing an entire payment, even though the balance was small. A larger down payment lowers the mortgage payment and helps the front-end ratio.
The flip side: if you are close to a limit, avoid new debt. Financing a car or a big purchase in the weeks before a mortgage application can tip you over and sink the approval.
DTI is only one piece of underwriting. Credit score, savings, employment history, and the specific program all matter, and limits vary — FHA loans, for instance, can allow higher ratios with compensating factors.
This calculator does not determine eligibility. Treat it as a planning estimate and confirm the requirements with a licensed mortgage professional for a formal assessment.
Conventional loans generally cap back-end DTI at 43–45%. FHA loans allow up to 50% with compensating factors. VA loans have no hard cap but prefer under 41%. Jumbo loans are stricter, often requiring under 43%.
DTI includes minimum credit card payments, car loans, student loans, personal loans, alimony, child support, and the proposed housing payment. Utilities, insurance, groceries, and subscriptions are excluded.
For a new mortgage application, use the proposed mortgage payment (PITI), not your current rent. Rent is not a debt — it disappears when you buy. Lenders substitute the proposed mortgage payment instead.
Either increase income or reduce monthly debt. Paying off a car loan or student loan before applying for a mortgage meaningfully reduces back-end DTI. A larger down payment reduces monthly mortgage payment and front-end DTI.
Front-end DTI counts only your housing payment against gross income and is often capped near 28%. Back-end DTI counts all recurring debt payments, including housing, and is the more important figure for most lenders, typically capped around 43%. This calculator shows both so you can see which one is the binding constraint.
Lenders use gross (pre-tax) monthly income, which is what this calculator expects. Because your take-home pay is lower than gross, a DTI that looks comfortable on paper can still feel tight in your actual budget — it is worth checking affordability against net income too.
Figures on this page are checked against primary, authoritative sources. Links open in a new tab.
Budget & credit disclaimer
These are planning estimates based on the numbers you enter. Interest rates, fees, and lender terms vary and change over time. This is educational information, not financial or credit advice.
Built and maintained by Calculator Matters, an independent calculator project. Method checked against published formulas and primary sources · Last reviewed 4 June 2026 · How we calculate · Found an error? corrections@calculatormatters.com