Debt-to-Income Ratio Calculator
Calculate the DTI ratio lenders use to decide whether to approve you.
Inputs
Before-tax income from all sources (employment, self-employment, rental, etc.).
P&I + taxes + insurance + HOA. Use proposed payment when applying for a mortgage.
Personal loans, child support, alimony, or any other recurring obligations.
Front-End DTI (Housing)
25.0%
Conventional limit: 28%. FHA limit: 31%.
Back-End DTI (All Debts)
40.0%
Conventional limit: 36%. FHA limit: 43%.
DTI Assessment
Acceptable (Conventional)
Total Monthly Obligations
$2,400.00
Headroom to Conventional 36% Limit
$0
Additional monthly debt you can take on and still qualify conventionally.
Headroom to FHA 43% Limit
$180
Passes Conventional Guidelines
false
Passes FHA Guidelines
true
Step by step
Gross monthly income
= $6,000.00
Total housing costs
= $1,500.00
All other monthly debt payments
$450.00 car + $300.00 student + $150.00 cards + $0.00 other
= $900.00
Front-end DTI (housing only)
$1,500.00 ÷ $6,000.00 × 100
= 25.0%
Conventional limit: 28% | FHA limit: 31%
Back-end DTI (all debts)
$2,400.00 ÷ $6,000.00 × 100
= 40.0%
Conventional limit: 36% | FHA limit: 43%
Assessment
= Acceptable (Conventional)
Exceeds conventional limits; may qualify under FHA (31/43).
How it works
Lenders calculate two DTI ratios. The front-end ratio compares your housing costs alone to your income — an overextended housing payment signals affordability risk. The back-end ratio adds all monthly debt obligations: it's the number underwriters rely on most. Conventional loans typically require both ratios under 28/36; FHA allows 31/43 with compensating factors. Both ratios use gross (pre-tax) income, not take-home pay.
Formulas
Front-end DTI
Front-end DTI = Housing payment / Gross monthly income × 100
- H
- Monthly housing costs (PITI)
- I
- Gross monthly income
Back-end DTI
Back-end DTI = (Housing + all other debts) / Gross monthly income × 100
- D
- All other monthly debt payments
Frequently Asked Questions
Which DTI number does my lender care about most?
Back-end DTI is the primary decision metric for most lenders. Front-end is a secondary check. Being within guideline on both ratios gives the strongest loan approval path; exceeding the back-end limit is the most common reason a mortgage application is denied.
Do I use gross or net income?
Always gross (before-tax) income. This is a lender convention, not financial advice — the actual budget impact on your household is better assessed using take-home pay. The Calculator intentionally uses gross because that's what mortgage underwriters use.
What counts as a debt payment?
Any recurring monthly obligation that appears on your credit report: mortgages, car loans, student loans, credit card minimums, child support, alimony, personal loans. It does not include utilities, groceries, phone bills or subscriptions, which lenders do not count.
Can a high credit score offset a high DTI?
Sometimes. Lenders may approve borrowers up to 45–50% back-end DTI with excellent credit (760+), significant cash reserves or a large down payment as compensating factors. FHA explicitly allows up to 57% DTI in some cases with strong compensating factors. VA loans are evaluated holistically.