Understanding Your DTI

Debt-to-income ratio, or DTI, is simple to calculate and easy to get wrong by omission. Add up your minimum monthly debt payments — car loans, student loans, credit card minimums, personal loans, any court-ordered payments — and divide by your gross monthly income, meaning income before taxes. The result is a percentage. A household earning $6,000 a month with $1,500 in monthly debt payments has a DTI of 25%.

The two mistakes people make are using net income instead of gross, which understates the ratio, and forgetting a debt that doesn't feel like debt — a 0% promotional car loan, a payment plan on a phone, a private loan from family with a real repayment schedule. Lenders count all of it. So does HōMI.

Lending convention has watched the same handful of DTI bands for decades — you will often hear 28/36/43 quoted — because those lines exist for real structural reasons, not tradition for its own sake. The lower your ratio sits beneath them, the more comfortably a mortgage payment fits alongside everything else you're paying down, with room left over for the month that doesn't go to plan.

HōMI's Financial Reality pillar pays attention to the same territory, scored against your margin rather than a lender's approval bar. Exactly how the bands translate into your score stays private — the signal is more honest when it can't be answered around. What never changes is the direction: every point of DTI you shed is real margin, and margin is what absorbs surprises.

Push the ratio high enough and the question stops being how much it costs your score. Past a certain line, HōMI treats an oversized debt load as a hard-stop: the verdict is forced to its most protective answer regardless of how strong your down payment, your credit, or your emotional readiness looks. The exact line stays private — naming it would tell you how to answer around it instead of how to fix it.

The reasoning is specific: at some point your monthly obligations leave almost no margin for the ordinary surprises of a life — a car repair, a medical bill, a slow month at work. It isn't that you can't make the payment this month. It's that you have no room to absorb the month that goes wrong, and eventually one does. That's a different kind of risk than a weak sub-factor, which is why it's treated differently.

Lenders care about DTI because it predicts default risk to them — will you make the payment. HōMI cares about the same number for a different reason: will making the payment cost you the rest of your financial life. A DTI that clears a lender's approval bar can still leave you with no room to save, to handle an emergency, or to feel anything other than stretched every month.

That's the gap HōMI is built to close. The lender's approval and your actual readiness are two different questions that happen to share one input number.

DTI moves in only two directions: pay down debt, or grow income, and the former is faster to control. Paying off a car loan with six months left can move your ratio more than a raise would, because it removes a fixed monthly obligation entirely rather than just growing the denominator.

For the practical, step-by-step version of this — how to size a target monthly payment against your real number, not the lender's maximum — see our guide, How Much House You Can Actually Afford. For how DTI fits alongside the other hard-stops, see The Four Hard Stops.