Debt-to-Income Ratio: What It Is and Why It Matters

Your debt-to-income ratio (DTI) is one of the most important numbers in your financial life, yet most people have never calculated it. DTI is simple: add up all your monthly debt payments and divide by your gross monthly income. If you earn $6,000 per month and your total debt payments are $2,000, your DTI is 33%.

There are actually two types of DTI. Front-end DTI only counts housing costs (mortgage or rent, property tax, insurance). Back-end DTI counts all monthly debt payments including housing, car loans, student loans, credit cards, and personal loans. When lenders say "DTI" they usually mean back-end.

Why does DTI matter so much? It is one of the top factors lenders use to approve or deny your loan applications. For conventional mortgages, most lenders require a back-end DTI under 43%. For the best rates, you want it under 36%. FHA loans allow up to 50% DTI in some cases, but higher DTI means higher risk and potentially higher interest rates.

To calculate your DTI, add up every monthly debt payment: mortgage or rent, car payment, minimum credit card payments, student loan payments, personal loan payments, and any other recurring debt obligations. Then divide by your gross monthly income (before taxes). Multiply by 100 for the percentage.

Here is what your DTI means in practice. Under 20% is excellent — lenders love you. Between 20 and 36% is good — you can qualify for most loans. Between 36 and 43% is concerning — you may struggle to qualify for a mortgage. Over 43% is problematic — most conventional lenders will deny you.

To improve your DTI, you have two levers: reduce your debt payments or increase your income. The fastest way to reduce payments is paying off small debts entirely (eliminating a $200 per month car payment drops your DTI significantly), consolidating high-interest debt to a lower rate, and avoiding taking on new debt. Increasing income through a raise, side hustle, or new job is the other side of the equation.

Use our free affordability calculator to see your exact DTI and find out the maximum purchase price you can afford.