How the Debt-to-Income Calculator Works

It calculates your debt-to-income (DTI) ratio — the share of your gross monthly income that goes to debt payments — which lenders use to judge how much mortgage you can carry.

How It Works, Step by Step

The calculator adds up your monthly debt obligations, including the proposed mortgage payment, and divides that total by your gross monthly income. It often shows both the front-end ratio (housing only) and the back-end ratio (all debts), since lenders look at both.

With no state income tax in Florida, your gross and net pay are closer together than in many states, but lenders still qualify you on gross income. Keep in mind that Florida's higher insurance and HOA costs raise the housing side of the ratio, so the same salary supports a slightly smaller loan than it would in a low-insurance market.

Want the underlying math? See the debt-to-income formula page, or open the calculator to try it with your own figures.