Advanced Debt-to-Income ratio calculator including front-end and back-end DTI calculations. Debt-to-income ratio requirements differ depending on the building.Debt-to-income (DTI) ratio is the percentage of your monthly gross income that is used to pay your monthly debt and determines your borrowing risk. Our calculator utilizes your annual and monthly income and expenses to provide you with an accurate DTI ratio. Another important calculation is the debttoincome ratio. Your ability to repay the loan will factor in your calculated debttoincome ratio and other monthly payments and bills that you may have. Calculate your debt-to-income ratio and find out what it means when you prepare to borrow. Toincome (DTI) ratio is a financial metric used to assess the financial health of an individual or household. Com) demonstrates how to calculate your debt-to-income ratio if you're buying a co-op apartment in NYC. Toincome (DTI) ratio is a financial metric used to assess the financial health of an individual or household.