CompoundInterestCalc
Free online tool · Real estate

Debt-to-Income Calculator

Use this free debt-to-income (DTI) calculator to see the number lenders check first. Enter your gross monthly income and your monthly debt payments, and get both your front-end and back-end DTI ratios instantly.

Your DTI is the single biggest factor in whether you'll qualify for a mortgage and how much you can borrow. See where you land on the lender scale and how much room is left in your budget. No account, no sign-up, no spreadsheet.

Monthly income
$
Monthly debt payments
$
$
$
$
$
Back-end DTI —
0%
Front-end DTI
0%
Total monthly debt
$0
Left after debts
$0
Lender scale (back-end)
0–36% Healthy
36–43% Manageable
43–50% Stretched
50%+ High risk
Where your income goes

Estimates are for illustration and education only — not a lending decision. Lenders count debts differently and also weigh credit, assets and loan type.

The math

How DTI is calculated

Debt-to-income compares your monthly debt payments to your gross (pre-tax) monthly income. Lenders look at two versions: the front-end ratio (housing only) and the back-end ratio (all debts) — the back-end is the one that usually decides your loan.

Front-end DTI = Housing payment ⁄ Gross monthly income × 100
Just your rent or mortgage, property tax and insurance.
Back-end DTI = All monthly debt payments ⁄ Gross monthly income × 100
Housing plus car, credit cards, student and personal loans, and other required payments.
Worked example. On $6,000 gross income with a $1,800 housing payment, the front-end DTI is 30%. Add $950 of car, card and loan payments for $2,750 total, and the back-end DTI is about 46% — over the usual 43% cap, so paying down a debt or two would help you qualify.
See it in action

DTI at different debt loads

Three household profiles. Load any one into the calculator and adjust from there.

Quick guide

How to use the DTI calculator

Three short steps. Change any field and both ratios and the gauge update instantly.

Step 1

Enter gross monthly income

Your total pay before taxes and deductions. Include steady extra income like a second job or reliable bonuses.

Step 2

Add your debt payments

Housing, car, credit card minimums, and student or personal loans — the required monthly payments, not balances.

Step 3

Read your ratios

The gauge shows your back-end DTI against the lender scale, with the front-end ratio and remaining budget alongside.

Step 4

Test paying debt down

Lower a debt payment to see how much your DTI improves — often the fastest way to qualify for more.

Good to understand

Why lenders care about DTI

Your debt-to-income ratio tells a lender how much of your income is already promised to debt — and therefore how much room you have to take on a mortgage payment. It's one of the most important numbers in underwriting, often mattering as much as your credit score.

Front-end vs back-end

The front-end ratio looks only at housing costs; a common guideline is to keep it at or below 28%. The back-end ratio includes all recurring debt, and most conventional mortgages want it at or below 43%, though some loan programs allow more. When people say "your DTI," they usually mean the back-end figure.

What counts as debt

Lenders count required monthly payments: mortgage or rent, property tax and insurance, auto loans, minimum credit-card payments, student and personal loans, and court-ordered payments like alimony. They generally don't count utilities, groceries, insurance premiums that aren't loan-related, or taxes withheld from pay.

How to lower your DTI

Two levers: reduce debt or raise income. Paying off a small loan or a card with a high minimum can drop your ratio quickly. Avoid taking on new debt (like a car loan) in the months before applying for a mortgage, since it directly raises your back-end DTI.

Who it's for

Anyone preparing to apply for a mortgage or large loan, or just checking their financial headroom. You only need your gross income and monthly debt payments.

Ready to see what you can afford? Try the mortgage affordability calculator, or browse all our free tools.

Quick answers

Debt-to-income calculator FAQ

Is this DTI calculator free?
Yes — it's completely free, runs entirely in your browser, and requires no account or sign-up. Your numbers are never sent to us or stored on a server.
What's a good debt-to-income ratio?
Lower is better. A back-end DTI at or below 36% is considered healthy, up to 43% is acceptable for most mortgages, and above that lenders get cautious. For housing alone (front-end), 28% or less is a common target.
Should I use gross or net income?
Gross — your income before taxes and deductions. That's what lenders use, so the DTI here matches how you'll be evaluated.
Does DTI include utilities and groceries?
No. DTI counts required debt payments only — housing, loans and minimum card payments. Everyday living costs like utilities, food and insurance premiums aren't included.
Is this financial advice?
No. This is an educational tool showing illustrative estimates. Lenders may count certain debts differently and weigh other factors. Always confirm with your lender.