Mortgage Dti Calculator

Reviewed by: David Chen, CFA. Last updated: Dec 4, 2025.

Use our free mortgage DTI calculator to quickly determine your Debt-to-Income (DTI) ratio, a crucial metric lenders use to assess your ability to manage monthly payments and repay a loan.

Mortgage DTI Calculator

Your Calculated Debt-to-Income (DTI) Ratio is: –%

Step-by-Step Calculation:

Mortgage DTI Calculator Formula

$$ \text{DTI Ratio} = \frac{\text{Monthly Debt Payments (PITI + Other Debts)}}{\text{Gross Monthly Income}} \times 100 $$

Formula Sources: CFPB, Investopedia

Variables

The DTI calculation uses three primary variables, all measured on a monthly basis:

• Monthly Housing Payment (PITI): The total of Principal, Interest, Property Taxes, and Hazard Insurance.
• Other Monthly Debt Payments: Minimum required payments for auto loans, student loans, credit cards, and other revolving or installment debt.
• Gross Monthly Income: Your total income before taxes, deductions, or withholdings.

What is Debt-to-Income (DTI) Ratio?

The Debt-to-Income (DTI) ratio is a personal finance measure that compares your total monthly debt payments to your gross monthly income. This ratio is expressed as a percentage. It is one of the key factors mortgage lenders evaluate to determine your borrowing capacity and the risk associated with lending you money.

A low DTI demonstrates that you have a good balance between debt and income, suggesting you are less likely to default on loan payments. Generally, a DTI of 43% is the highest a borrower can have and still qualify for a qualified mortgage (QM), though many conventional lenders prefer a DTI below 36%.

How to Calculate DTI (Example)

1. Determine Total Monthly Debt: Sum your monthly housing payment (PITI) and all other minimum required debt payments. (Example: $1,800 PITI + $400 Car Payment + $50 Credit Card Min. = $2,250)
2. Determine Gross Monthly Income: Find your total income before any taxes or deductions are taken out. (Example: $6,500)
3. Apply the Formula: Divide your total monthly debt by your gross monthly income. (Example: $2,250 / $6,500 = 0.346)
4. Convert to Percentage: Multiply the result by 100 to get the DTI ratio. (Example: 0.346 x 100 = 34.6%)

Related Calculators

Explore other financial tools to help manage your home buying process:

• Home Affordability Calculator
• Closing Cost Estimator
• Mortgage Amortization Schedule
• Mortgage Tax Deduction Calculator

Frequently Asked Questions (FAQ)

What is a good DTI ratio for a mortgage?

A DTI ratio of 36% or lower is generally considered good. Ratios below 20% are excellent. While many lenders accept up to 43% for conventional loans, aiming lower improves your chances for better interest rates.

Does DTI include utilities?

No, the DTI ratio generally does not include living expenses like utilities, groceries, gas, or insurance premiums (other than the PITI insurance). It focuses strictly on recurring monthly debt obligations.

How can I lower my DTI?

You can lower your DTI by either increasing your gross monthly income (e.g., getting a raise or second job) or, more commonly, by reducing your total monthly debt payments (e.g., paying off credit cards or closing loans).

Is the DTI calculation based on gross or net income?

The DTI calculation is always based on your Gross Monthly Income (income before taxes and deductions) because it provides a lender with the clearest picture of your total earning capacity.