How to use the DTI calculator
- Enter gross annual income (household total if applying jointly).
- Enter monthly housing payment—P&I plus whatever fixed housing costs you treat as part of this line (tax/insurance/HOA if you bundle them).
- Enter other monthly debt: auto, student loans, minimum credit card payments, personal loans—not utilities or food.
- Read front-end (housing ÷ income), back-end (housing + other ÷ income), and total monthly debt.
- To solve for max home price from income, use the house affordability calculator; this page checks DTI when you already have a payment in mind.
Front-end vs back-end DTI
Lenders often discuss both ratios. The 28% / 36% hints on this page are common planning guides, not approval guarantees.
Example
$120,000 gross income → $10,000/month. Housing $2,300 and other debt $500 → 23% front-end, 28% back-end. Raise other debt to $1,500 and back-end becomes 38% even if housing is unchanged.
Workflow with mortgage tools
Estimate P&I in the mortgage calculator, check DTI here, then max price in affordability. Refinance payment changes pair with the mortgage refinance calculator.
Frequently asked questions
What are front-end and back-end ratios?
Front-end is housing payment ÷ gross monthly income. Back-end adds other fixed monthly debt payments. Lenders often review both; rules vary by market and product.
What goes in the housing payment field?
Enter the fixed housing cost you carry or plan: often mortgage P&I, sometimes PITI or rent if you bundle tax, insurance, and HOA in one line. This page takes one number—it does not split escrow for you. Estimate P&I in the mortgage calculator first if needed.
What counts as other monthly debt?
Include auto, student loans, minimum credit card payments, personal loans, and similar fixed installments. Usually exclude utilities, food, and discretionary subscriptions. If a loan pays off soon, try zero or the post-payoff payment to see back-end change.
What does the 28% / 36% guide mean?
Common US-style planning guides: housing near 28% and total fixed debt near 36% of gross income. Exceeding the guide does not auto-deny a loan; meeting it does not guarantee approval—credit, down payment, and reserves matter too.
How is this different from affordability?
The affordability calculator solves backward for max price or payment from income and debts. This page checks ratios when you already have a housing payment in mind—often after a mortgage estimate.
Gross or net income?
This page uses gross (pre-tax) annual income divided by 12—the usual mortgage worksheet basis. Do not enter take-home pay as if it were gross. Self-employed users often use a recent annual gross average.
Do ratios change after refinance or moving?
Yes—any housing payment change moves both ratios. After a mortgage refinance, plug the new payment here and refresh other debt if auto or card payments changed.
Can I share my scenario?
Yes. Use copy link below the form to share the same numbers with someone else or keep the scenario for your records.