What Is Debt-to-Income Ratio (DTI)? If you’re buying a home, one of the most important numbers a lender looks at is your Debt-to-Income Ratio, also called DTI. This single percentage can determine whether you get approved, how much you can buy, and what loan programs you qualify for. In simple terms: DTI = How much you owe every month ÷ How much you earn every month It measures how “stretched” your finances are before a bank agrees to give you a mortgage. Why Debt-to-Income Ratio Matters When Bu