Mortgage Guide

Affordability

Debt-to-Income Ratio, Explained

Published by the Mortgage Guide editorial team. Rate assumptions and content updated October 2026. This page is educational. It is not a loan offer, approval, or personalized financial advice.

Which debts go in

Use car loans, card minimums, student loans, and other debts that will continue. Do not add the rent you will leave behind if the housing line is the new mortgage.

Lenders decide how to document student loans and authorized-user cards. The calculator uses the monthly numbers you type.

Read the words, not a color

The page describes under 36%, between 36% and 43%, and above 43% in sentences. Those bands are labels for a conversation, not a decision.

Older mortgage rules talked about 43%. Current loan programs set their own caps. Do not treat 43% as a hard stop or a guarantee.

The two ratios
RatioNumerator
Front-endHousing only
Back-endHousing plus other debts

Calculators

Related guides

Sources

Common questions

Do I use net income?

No. DTI uses gross monthly income, before taxes are withheld.

Does a high score erase a high DTI?

Credit and DTI are separate. A calculator that shows one of them is not measuring the other.