DTI stand for Debt To Income ratio. It is calculated by taking your monthly debt and dividing by your monthly income.
Your DTI or debt to income ratio is one of the most important factors in calculating how much of a home you can afford or qualify for. By calculating your DTI a mortgage broker is able to find out how much money you have left or available each month that you can use for a mortgage payment.
Many subprime lenders will allow up to a 50% DTI or debt-to-income ratio. A few will even go up to 55%.