How to Use the DTI Calculator

This DTI calculator compares the mortgage and debt payments you enter with your income before taxes. Follow these steps, then change one input at a time to compare scenarios.

Step 1: Enter income before taxes

Choose annual or monthly income, then enter your gross income. For a $96,000 annual salary, select Annual income and enter 96,000. Add a co-borrower’s income using the same units, or enter $0. For self-employed, rental or variable income, use a lender-calculated figure when available. Business sales or deposits are not automatically qualifying income.

Step 2: Enter the complete housing payment

Choose Calculate from loan details to enter the financed loan amount, a hypothetical rate and the term. Enter taxes, property insurance and flood insurance as annual amounts. Mortgage insurance, HOA and other housing obligations are monthly. Mortgage insurance is entered manually; the calculator does not determine the premium.

If you know your complete monthly housing payment, choose the second option and enter that total. Include principal, interest, taxes, insurance, mortgage insurance, HOA and any applicable second-loan payment. Do not enter principal and interest alone.

Step 3: Enter other monthly debt payments

Enter required payments for car loans, credit cards, student loans, support and other debts. Use credit-card minimum payments, not balances. Student-loan qualification may use a different amount than your current payment, including when deferred. Do not count the proposed housing payment twice. Include retained-property obligations as the lender treats them; do not automatically subtract gross rent.

Living costs such as groceries, childcare, utilities and savings goals still matter to your budget even though they are not ordinary debts in this DTI model.

Step 4: Choose your comparison targets

The total DTI target controls the percentage of income modeled for housing plus debts. The initial 45% is an editable example, not a lender requirement. You can also enter an optional housing-only target. Leave that box blank to use only the total target. When both are entered, the calculator uses the more restrictive housing allowance.

Step 5: Select Calculate DTI

Total DTI includes the proposed housing payment plus other debts. The housing-only ratio includes just housing. Income needed estimates the gross income required to meet your selected targets. Supported housing estimates the payment those targets allow after other debts.

The loan amount estimate appears only when you enter loan details. It keeps taxes, insurance, mortgage insurance and dues constant. It does not apply purchase-price, down-payment, LTV or lender limits, and a different loan amount can change mortgage insurance.

Step 6: Compare changes or request a review

Change a payment, income amount or target and select Calculate DTI again. To discuss your situation, use the review form or Text a Question. Contact details are not required to calculate, and sharing the numbers with a request is optional.

Example DTI calculation

With $8,000 gross monthly income, $2,500 total housing and $1,000 other monthly debts, total DTI is 43.75%. Housing alone is 31.25%. At a 45% total target with no housing-only target, the modeled housing allowance is $2,600 and the monthly income needed for the original payments is $7,777.78.

Formula and important assumptions

Total DTI = (monthly housing + other monthly debt payments) ÷ gross monthly income × 100. These results use your entered income and obligations. Loan programs may treat income, student loans, support, rental properties and qualifying payments differently. Zero income produces an undefined ratio. The tool does not evaluate credit, reserves, residual income, AUS or approval.

Related 210 Mortgage guides

• Understand debt-to-income ratio for a mortgage
• Learn how qualifying mortgage income is evaluated