Before a lender looks at your credit score, your down payment, or the house, they run two debt-to-income ratios. One is how much of your income the house payment alone would take (front-end). The other is how much of your income goes to the house plus all your other monthly debts (back-end). Together they decide whether you get approved, and how much you can borrow. This calculator checks your numbers against conventional, FHA, and VA guidelines and shows exactly how much house your monthly debts are costing you.
What you’ll learn
- Your front-end and back-end DTI ratios
- The max housing payment each program allows you
- Whether your target payment fits, program by program
- How much buying power each monthly debt costs
- The fastest DTI fixes before you apply
Check your mortgage DTI
Enter your gross monthly income and debt payments. Add the housing payment you have in mind to check it against each program. Your inputs are saved in your browser.
Mortgage DTI Calculator
See your front-end and back-end ratios and which loan programs your numbers fit.
Before taxes, all borrowers
Cards, car, student loans. Not rent
Full PITI. Optional
Every $100 of payments you clear unlocks about $15,000 more house. Debt Driver picks which ones to kill first.
Get My Personalized Plan →Front-end vs back-end
Mortgage underwriters run two ratios on every file, and you must pass both. The front-end ratio checks the house payment alone; the back-end ratio checks the house plus everything else you owe each month.
Front-end DTI
Housing / gross income
The full housing payment: principal, interest, property taxes, homeowners insurance, HOA dues, and mortgage insurance if any. Classic guideline: 28% or less.
Back-end DTI
Housing + debts / gross income
Everything above plus card minimums, auto loans, student loans, and other required payments. This is the number that usually decides your approval.
DTI limits by loan type
Each program has a guideline ratio and a stretched maximum that requires compensating factors like strong credit, reserves, or a bigger down payment:
| Loan type | Guideline | Stretched max |
|---|---|---|
| Conventional | 28 / 36 | Up to 50% back-end |
| FHA | 31 / 43 | 46.9 / 56.9 |
| VA | 41% back-end | Higher with residual income |
| USDA | 29 / 41 | Modest with strong credit |
Two cautions: individual lenders add their own stricter overlays, and qualifying at a stretched maximum means a payment that eats half your gross income. The guideline column is where the payment stays livable. Not sure where your overall DTI stands outside of a mortgage? Start with the general DTI calculator.
What your debts cost you
Monthly debt payments do not just lower your DTI number. They directly shrink the house you can buy. Here is a buyer with $8,000 gross monthly income at a 36% back-end limit, 7% rate, 30-year term, with $500/mo going to taxes and insurance:
| Monthly debts | Max housing payment | Approx. loan size |
|---|---|---|
| $0 | $2,240 | ~$262,000 |
| $800 | $2,080 | ~$237,000 |
| $1,200 | $1,680 | ~$177,000 |
| $1,600 | $1,280 | ~$117,000 |
Read that middle jump again: going from $800 to $1,200 in monthly debts, roughly one car payment, cuts the loan by about $60,000. Once the back-end limit is what caps you, every $100 of monthly payments costs about $15,000 of mortgage at 7%. Paying off a loan before you apply is often worth more than a year of extra saving for the down payment.
How to lower DTI fast
1.Pay off the biggest payments, not the biggest balances
DTI counts monthly payments. A $6,000 car loan with a $400 payment hurts your ratio more than $10,000 of credit card debt with $250 in minimums. Target the largest payment you can fully eliminate.
2.Knock installment loans to under 10 payments
Conventional guidelines often let lenders exclude installment debts with 10 or fewer payments remaining. Paying a car loan down from 14 payments to 9 can erase it from your DTI without paying it off entirely.
3.Get student loan payments documented
Deferred loans get counted at 0.5 to 1 percent of the balance. An income-driven repayment plan with a low documented payment can slash the number lenders must use.
4.Do not finance anything before closing
A new car, furniture on credit, or even a large new card balance between pre-approval and closing changes your DTI, and lenders re-check. Buy the couch after you get the keys.
House hunting next year? A payoff plan now is down payment power later.
Get My Personalized Plan →FAQs
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Open →Auto Loan Payoff Calculator
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Open →Interest Savings Calculator
See what any extra payment saves you in interest.
Open →Clear the path to yes
Pay off the right debts first and walk into the lender with room to spare.
Get My Personalized Plan →Debt Driver is a debt payoff planning app. We are not a lender, mortgage broker, or credit counselor. The ratios, program limits, and loan estimates above are illustrative guidelines; actual underwriting varies by lender, program, credit profile, rates, and location. Confirm current requirements with a licensed mortgage professional. Nothing here is financial, lending, or legal advice.