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Debt-to-Income Ratio Calculator

Your debt-to-income ratio is the single number lenders read first. Enter your gross monthly income and your minimum monthly debt payments — the calculator does the DTI math and tells you where you stand.

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Your debt-to-income ratio

Use gross monthly income (before taxes) and your minimum required monthly payments — not what you actually pay. Most lenders use the 36% line as their first cut.

How it works: DTI = total minimum monthly debt payments ÷ gross monthly income × 100. Lenders usually count housing, auto, credit-card minimums, student loans, child support and other required payments — but not utilities, insurance, taxes withheld, or discretionary spending. This calculator uses the back-end ratio (all debts); lenders also watch the front-end ratio (housing only), shown in the tiles. Nothing you type leaves your device.

What the ratio actually tells a lender

Your debt-to-income ratio answers the lender's real question: how much of this person's income is already spoken for? Credit score measures whether you pay; DTI measures whether you can pay. That's why mortgage underwriters read it first — a perfect 800 score with a 55% DTI still gets a no.

Output · formula · meaning

Output	Formula	What it means
Back-end DTI	all minimum payments ÷ income × 100	The headline number. Under 36% = lender-comfortable; over 43% = most mortgages denied.
Front-end DTI	housing payment ÷ income × 100	Housing alone. Lenders like ≤ 28% — it's the first half of the classic 28/36 rule.
Max new debt at 36%	36% × income − current payments	How much more monthly debt you can take on and stay at the lender line.
Breathing room at 43%	43% × income − current payments	Room left before the mortgage cutoff — the absolute ceiling for most home loans.

Worked example: the 37.9% household

Maya earns $7,500/month gross. Her minimums: housing $1,900, auto $420, credit cards $160, student loans $310, other $50 — total $2,840. DTI = 2,840 ÷ 7,500 × 100 = 37.9%. She's just over the 36% lender line: her max new debt at 36% is −$140/month, meaning she needs to shed $140 of monthly payments (or raise income ~$390) before a mortgage underwriter is comfortable. Front-end: 1,900 ÷ 7,500 = 25.3% — the housing half is fine; it's the auto + student loans that push her over.

Who uses this

Home buyers: the 28/36 rule decides your mortgage ceiling — check before you fall in love with a house.
Car shoppers: a new payment lands in the same total — see the DTI impact before the dealer runs it.
Debt payers: watch the ratio fall as you kill balances — it's the most motivating number in a payoff plan.
Renters applying: some landlords screen on affordability ratios too — know yours before the application.

Accuracy & limitations

This uses minimum required payments and gross income, matching standard underwriting — but real lenders differ. Mortgage lenders add property taxes, insurance, and HOA to the housing figure and may count deferred student loans differently; auto lenders often use looser caps. DTI also ignores assets, savings rate, and income stability — it's a cash-flow snapshot, not a full financial picture.

Pair it with the debt payoff comparison to choose your attack order, and the debt-to-income guide to move the number down.

Cite this pageBright Side Kit. “Debt-to-Income Ratio Calculator.” brightoolbox.com, 2026.

Bright Side Kit. "Debt-to-Income Ratio Calculator." https://brightoolbox.com/debt-ratio-calculator/ Accessed October 21, 2026.

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Frequently asked questions

What is a good debt-to-income ratio?

Under 20% is excellent, 20–35% is manageable, and under 36% is the line most lenders want to see. 36–43% is the caution zone — some loans still work, but rates and scrutiny rise. Over 43–50% means most mortgage approvals stop, and over 50% signals serious cash-flow stress.

What is the 28/36 rule?

Mortgage shorthand: keep housing (front-end) under 28% of gross income and all debts (back-end) under 36%. Many lenders now stretch to 43–45% back-end for strong borrowers, but 28/36 is still the conservative target that leaves real breathing room.

Do lenders use gross or net income for DTI?

Gross — income before taxes and deductions. Using take-home pay makes the ratio look worse than a lender would compute it. If you're not sure of your gross, multiply a biweekly gross paycheck by 2.1667 or divide your salary by 12.

Does my credit card balance count if I pay it off monthly?

Standard underwriting uses the minimum required payment, so a card you pay in full counts as $0 (or a tiny minimum on some reports). The balance itself matters for your credit score via utilization, not for DTI.

How can I lower my DTI fast?

Three levers: pay down balances (kills minimums), refinance to longer terms or lower rates (smaller payments, more total interest), and raise income (overtime, a raise, a side gig). Paying off a whole loan helps most — a $310 student-loan payment removed is worth more than $310 off a card balance. The full playbook is in the debt-to-income guide.

What DTI do I need for a mortgage?

Conventional loans generally cap back-end DTI at 45% (36% preferred); FHA allows up to about 56.9% with strong compensating factors; VA loans are flexible but flag ratios above 41%. These are maximums, not targets — qualifying at 50% leaves almost no margin.

Does DTI include utilities, insurance, or taxes?

No — only required debt payments: housing (PITI + HOA), auto, credit-card minimums, student loans, child support, alimony, and other installment debts. Utilities, subscriptions, groceries, and discretionary spending don't count (which is why two identical DTIs can feel very different).