Debt-to-Income Ratio (DTI)
Definition
The debt-to-income ratio (DTI) compares a borrower's monthly debt obligations to their gross monthly income. It is used by lenders to determine how much mortgage a borrower can afford.
Example
A borrower earns $8,000/month gross. Proposed PITI is $2,000, car payment is $400, and student loans are $200. Front-end DTI = $2,000 / $8,000 = 25%. Back-end DTI = ($2,000 + $400 + $200) / $8,000 = 32.5%. Both are within conventional guidelines.
Exam Tip
Always use GROSS (pre-tax) income, never net income. Memorize conventional thresholds: 28% front-end and 36% back-end. The front-end ratio includes only housing costs; the back-end includes all recurring debts. If either ratio exceeds the guideline, the borrower may not qualify.
Related Financing Terms
Conventional Loan
A conventional loan is a mortgage that is not insured or guaranteed by a government agency such as the FHA, VA, or USDA. It is originated and funded by private lenders and may be conforming or non-conforming.
FHA Loan
An FHA loan is a mortgage insured by the Federal Housing Administration that allows lower down payments and credit scores than conventional loans. It is designed to help first-time homebuyers and borrowers with limited resources.
VA Loan
A VA loan is a mortgage guaranteed by the Department of Veterans Affairs available to eligible veterans, active-duty service members, and surviving spouses. It offers no down payment and no private mortgage insurance requirements.
Fixed-Rate Mortgage
A fixed-rate mortgage has an interest rate that remains constant for the entire term of the loan, resulting in equal monthly principal and interest payments throughout the life of the mortgage.
Adjustable-Rate Mortgage (ARM)
An adjustable-rate mortgage (ARM) has an interest rate that changes periodically based on market conditions, typically after an initial fixed-rate period. The rate adjustment is tied to a financial index plus a margin.
Loan-to-Value Ratio (LTV)
The loan-to-value ratio (LTV) is the percentage of a property's appraised value or purchase price (whichever is lower) that is being financed through a mortgage. LTV = Loan Amount / Property Value.
Frequently Asked Questions
Test Your Financing Knowledge
Practice with exam-style questions to make sure you can apply Debt-to-Income Ratio (DTI) and other financing concepts.