Debt-to-income ratio: how lenders look at your borrowing

ReviewedEducational article · Updated Oct 2026

Key takeaways

DTI is monthly debt payments divided by gross monthly income.
Lenders use it as one measure of whether you can afford a new loan.
Front-end DTI looks at housing costs only; back-end DTI includes all debts.
You can improve DTI by reducing debt payments or increasing income.

When you apply for a mortgage, car loan or personal loan, the lender wants to know whether you can afford the repayments. One of the first measures they look at is your debt-to-income ratio, or DTI. You can calculate it in a couple of minutes.

The formula

DTI = Total monthly debt payments ÷ Gross monthly income × 100

Gross income means before tax. Debt payments are the required monthly amounts on loans, credit cards (usually the minimum), and housing costs, depending on which version you use.

Front-end and back-end ratios

Front-end ratio: housing costs only (mortgage or rent, property tax, insurance) divided by gross income.
Back-end ratio: all monthly debt payments, including housing, car loans, student loans and card minimums, divided by gross income.

A worked example

Suppose your gross income is $6,000 a month and your monthly obligations are:

Mortgage payment (including tax and insurance): $1,400
Car loan: $350
Student loan: $250
Credit card minimum: $100

Front-end DTI = 1,400 ÷ 6,000 = 23.3%. Back-end DTI = (1,400 + 350 + 250 + 100) ÷ 6,000 = 2,100 ÷ 6,000 = 35%.

35%

In this example, 35 cents of every gross dollar of income goes to debt payments.

What lenders do with it

Lenders set their own limits, and thresholds vary by country, loan type and lender. As a rough orientation, many consumer lenders become more cautious as the back-end ratio climbs into the high 30s or the 40s percent, but there is no universal cut-off. Always check with the lender you are applying to.

How a new loan changes the ratio

Adding a $15,000 car loan over 36 months at 7.9% would add roughly $469 a month. In the example above, the back-end DTI would rise from 35% to (2,100 + 469) ÷ 6,000 = 42.8%. You can compute a monthly payment for a prospective loan with the loan EMI calculator and see how it changes your own ratio.

Ways to improve your DTI

Pay down balances, especially those with high monthly payments. See snowball vs. avalanche.
Avoid new debt before applying for a large loan.
Increase income, or include a co-applicant’s income if the lender allows it.
Choose a longer term to lower the monthly payment, remembering that this raises total interest. See EMI and amortisation.

What DTI does not tell you

DTI ignores your spending on food, childcare, utilities and everything else, so a ratio that a lender accepts may still feel tight in practice. It also says nothing about savings. Think of it as a floor for lender comfort, not a target for what you should borrow. Compare it with your own budget; the 50/30/20 rule is one way to check.

Common questions

Does rent count?

For a mortgage application, lenders may use your proposed housing payment instead of your current rent. For other loans they may count rent or ignore it, depending on their rules.

Do utilities and groceries count?

No. DTI includes only debt obligations and housing costs.

Is DTI the same as my credit score?

No. A credit score reflects your repayment history; DTI reflects how much of your income is already committed. Lenders usually look at both. This article is educational, not personal advice.

Common mistakes to avoid

Using net income when the lender expects gross.
Leaving out minimum card payments or student loans.
Taking out a new loan just before applying for a mortgage.
Treating the lender’s maximum as your comfortable amount.

Quick glossary

Gross income: Income before tax and deductions.
Front-end ratio: Housing costs divided by gross income.
Back-end ratio: All debt payments divided by gross income.
Obligation: A recurring required payment.

Try it yourself

Add up your monthly debt payments, divide by your gross monthly income, and multiply by 100. Then add the payment for a loan you are considering and see how the figure changes.