Calculator Inputs
Enter monthly amounts. The result appears above this form after submission.
Example Data Table
| Scenario | Gross Income | Housing Payment | Other Debts | Guideline | Front-End DTI | Back-End DTI | Result |
|---|---|---|---|---|---|---|---|
| Example A | $8,500.00 | $2,175.00 | $525.00 | Conventional 28/36 | 25.59% | 31.76% | Pass |
| Example B | $6,200.00 | $2,050.00 | $800.00 | FHA 31/43 | 33.06% | 45.97% | Needs Adjustment |
| Example C | $9,400.00 | $2,450.00 | $420.00 | USDA 29/41 | 26.06% | 30.53% | Pass |
Formula Used
1) Housing Payment
Housing Payment = Principal & Interest + Property Tax + Home Insurance + HOA Dues
2) Front-End DTI
Front-End DTI (%) = (Housing Payment ÷ Gross Monthly Income) × 100
3) Back-End DTI
Back-End DTI (%) = ((Housing Payment + Other Monthly Debts) ÷ Gross Monthly Income) × 100
4) Maximum Housing by Front-End Limit
Max Housing = Gross Monthly Income × Front-End Limit
5) Maximum Housing by Back-End Limit
Max Housing = (Gross Monthly Income × Back-End Limit) − Other Monthly Debts
The calculator compares your actual ratios against the selected limits, then shows a recommended housing cap using the tighter of the two rules.
How to Use This Calculator
- Enter your gross monthly income before taxes and deductions.
- Add your proposed principal and interest payment.
- Enter monthly property tax, insurance, and HOA dues.
- Include all other recurring monthly debt obligations.
- Select a guideline set or choose custom limits.
- Click Calculate DTI Limits to see the result above the form.
- Review the ratio cards, detailed table, and graph.
- Use CSV or PDF export to save your current scenario.
Frequently Asked Questions
1) What is front-end DTI?
Front-end DTI measures only housing-related costs against gross monthly income. It usually includes principal, interest, taxes, insurance, and HOA dues when applicable.
2) What is back-end DTI?
Back-end DTI includes housing costs plus other recurring debts, such as car loans, student loans, credit card minimums, and personal loan payments.
3) Why do lenders use both ratios?
Front-end DTI checks housing affordability. Back-end DTI checks your total debt load. Using both helps lenders judge whether the payment is manageable from two different angles.
4) Which debts should I include?
Include monthly obligations that appear on credit or legal repayment records. Typical examples are auto loans, student loans, credit card minimums, installment loans, alimony, and child support.
5) Does a lower DTI always mean approval?
No. Approval also depends on credit profile, assets, property details, documentation, reserve funds, and underwriting rules. Lower ratios simply strengthen the affordability picture.
6) Should I use gross or net income?
Standard DTI calculations usually use gross monthly income, not take-home pay. Gross income gives a consistent underwriting base across borrowers and programs.
7) Why can the recommended housing cap be lower than expected?
The recommended cap uses the tighter result between front-end and back-end rules. High non-housing debts often reduce the housing amount allowed under the back-end test.
8) Is this calculator a lending decision?
No. This tool is for planning and education. Final lending decisions depend on the actual loan program, lender overlays, documentation quality, and complete underwriting review.