Should I use gross or net income?

Use gross. Lenders underwrite DTI on gross income. Net is better for personal budgeting but not DTI tests.

Do I include taxes/insurance in housing?

Yes—use full PITI and HOA. Lenders include them for DTI.

How are student loans counted?

Lenders may use the actual payment or a percentage of balance if in deferment/IDR. This tool uses your entered payment—enter a conservative number.

Does this guarantee approval?

No. DTI is one factor. Credit, assets, LTV, employment history, and program rules also matter.

How do deferred student loans count?

Some lenders use a percent of the balance (e.g., 0.5–1%) if no payment is reported. This tool uses your entered payment—enter a conservative estimate if deferred.

What about joint borrowers?

Combine gross incomes and all debts for both borrowers to get a household DTI. Lenders usually assess combined DTI for co-borrowers.

Do utilities or childcare count?

Typically not in DTI, but they matter for your real budget. Include them separately when assessing affordability.

finance calculator

Debt-to-Income (DTI) Calculator

Calculate front-end and back-end DTI ratios from your housing payment and other monthly debts versus gross monthly income.

Results

Front-end DTI: 31.25%
Back-end DTI: 37.50%

Overview

Debt-to-income (DTI) ratios are one of the first snapshots underwriters look at when they decide how much you can safely borrow. This calculator focuses on the two DTI flavors lenders care about most: front-end DTI, which looks only at your housing costs, and back-end DTI, which looks at housing plus all of your other recurring debts.

Instead of waiting until you are deep into a pre-approval or refinance to find out that your ratios are too high, you can plug in your gross monthly income, proposed housing payment, and other monthly debts here. The calculator instantly shows where you land relative to common program guidelines, so you can decide whether you need to pay down debt, adjust your price range, or add a co-borrower before you apply.

How to use this calculator

Enter gross monthly income.
Enter your housing payment (PITI/HOA) and other monthly debts (loans, cards, etc.).
Review front-end and back-end DTI percentages.
Adjust housing or debt inputs to see how payoffs or lower payments change DTI.

Inputs explained

Gross monthly income: Income before taxes and deductions, used by lenders for DTI.
Housing payment (PITI/HOA): Mortgage principal + interest + taxes + insurance + HOA (or rent).
Other debts: Minimum payments on credit cards, auto/student/personal loans, etc.

Outputs explained

Front-end DTI: Housing-only ratio (PITI ÷ gross monthly income).
Back-end DTI: Housing plus other debts ÷ gross monthly income.

How it works

Front-end DTI = housing payment ÷ gross monthly income.

Back-end DTI = (housing payment + other debts) ÷ gross monthly income.

Formula

Front-end DTI = housingPayment ÷ grossMonthlyIncome. Back-end DTI = (housingPayment + otherDebts) ÷ grossMonthlyIncome. Results expressed as percentages.

When to use it

Pre-checking mortgage eligibility against common DTI caps (e.g., 28/36 or 31/43).
Testing how paying off a loan impacts back-end DTI.
Comparing DTI before refinancing or adding a HELOC.
Seeing how a bigger down payment (lower PITI) affects qualification room.
Deciding which debt to pay off first to drop below a DTI threshold.
Checking how a new auto loan would impact homebuying readiness.
Assessing whether a co-borrower’s income/debts improves DTI enough to qualify.
Gauging how student loan repayment plan changes could shift DTI.

Tips & cautions

Front-end often targets ~28–31%; back-end often must stay under 36–45% depending on program (FHA, VA, conventional).
Paying down or consolidating debt can lower back-end DTI quickly.
Include taxes/insurance/HOA in housing for accuracy; lenders will.
If self-employed or variable income, lenders may average 12–24 months—use a conservative income number.
Small-payment loans might not move DTI much; target the largest payments for payoff impact.
If rates drop and you refi other loans, rerun DTI with lower payments to see if you qualify for more house.
Removing a $300 payment can be more powerful than shaving $20 off multiple debts—prioritize by monthly impact.
Consider term changes: longer term lowers payment but may increase total interest; balance DTI needs vs cost.
If you expect a bonus, don’t count it unless a lender would—be conservative to avoid surprises in underwriting.
Some programs count HELOC payments as a percent of the line; enter the lender’s assumed payment if known.
If your housing payment will change (tax reassessment, HOA increase), model the higher number to stay safe.
Does not include lender-specific add-ons (e.g., student loan imputed payments, alimony/child support rules).
Uses gross income; some programs adjust income for self-employed borrowers.
Does not consider reserves, credit score, LTV, or property type—other key approval factors.
No stress-testing for rate hikes on ARMs or future debts.
Child support/alimony treatment varies; enter as debts here if you want them included.
Does not model income averaging for bonuses/overtime; enter a conservative gross if variable.
Does not include non-debt obligations like childcare or medical costs, which affect real affordability.
Does not enforce specific program caps or compensating factors; check exact guidelines with your lender.

Worked examples

Typical FHA-style target

Gross income $8,000; Housing $2,000; Other debts $600.
Front-end = 2,000 ÷ 8,000 = 25%. Back-end = (2,000 + 600) ÷ 8,000 = 32.5%.
Fits common 31/43 FHA guidance comfortably.

High back-end due to auto loan

Gross $7,000; Housing $2,200; Other debts $1,000 (large auto + cards).
Front-end ≈ 31.4%; Back-end ≈ 45.7%.
Paying off/refinancing the auto could drop back-end below many lender caps.

Testing payoff effect

Start: Gross $9,000; Housing $2,400; Other debts $900 → Back-end ≈ 36.7%.
If $300 card payment is cleared, other debts drop to $600 → Back-end ≈ 33.3%.
Shows how targeted payoff can improve qualification room.

Impact of higher HOA

Gross $10,000; Housing $2,300 with $300 HOA; Other debts $700.
Front-end ≈ 23%; Back-end ≈ 30%.
If HOA rises to $500, housing = $2,500 → Front-end 25%, Back-end 32%—still okay but closer to caps.

Self-employed conservatism

Gross (conservative averaged) $6,500; Housing $1,800; Other debts $700.
Front-end ≈ 27.7%; Back-end ≈ 38.5%.
Using a conservative income avoids overestimating capacity if underwriters average income lower.

Adding a co-borrower

Borrower A: Gross $5,000; debts $900. Borrower B: Gross $3,000; debts $200. Proposed housing payment = $2,100.
Combined gross income = $8,000; combined other debts = $1,100.
Front-end DTI = 2,100 ÷ 8,000 = 26.25%; Back-end DTI = (2,100 + 1,100) ÷ 8,000 = 3,200 ÷ 8,000 = 40%.
Interpretation: adding a co-borrower with modest debts and solid income brings ratios into a range that may qualify for more programs than Borrower A alone.

Deep dive

Debt-to-income ratios drive mortgage approvals. This calculator shows front-end DTI (housing only) and back-end DTI (housing plus all recurring debts) so you can see where you stand against common lending thresholds before you ever talk with a loan officer.

Enter your income, PITI or rent, and all monthly debts to learn how much room you have or how much debt to pay down before applying. Use it to plan refis, HELOCs, or home purchases with clearer expectations and fewer last-minute surprises in underwriting.

Model payoff and consolidation scenarios to see if you can meet lender DTI caps by eliminating a single high-payment loan versus spreading extra cash across multiple smaller balances. The side-by-side front-end and back-end outputs make it clear which change moves the needle most.

Test higher or lower housing payments, HOA dues, or insurance estimates to understand affordability before shopping. You can pair this DTI tool with a home affordability or mortgage payment calculator to align what you feel comfortable paying with what underwriters are likely to approve.

Check how a new car loan, personal loan, or consolidation loan would impact your DTI before signing. A payment that feels small in your monthly budget can still push back-end DTI above key program cutoffs if your income is tight.

Plan a refinance by seeing whether your current debts keep you within program back-end limits at today’s rates, and whether paying down or restructuring specific obligations could open up better pricing or more flexible loan options.

FAQs

Should I use gross or net income?: Use gross. Lenders underwrite DTI on gross income. Net is better for personal budgeting but not DTI tests.
Do I include taxes/insurance in housing?: Yes—use full PITI and HOA. Lenders include them for DTI.
How are student loans counted?: Lenders may use the actual payment or a percentage of balance if in deferment/IDR. This tool uses your entered payment—enter a conservative number.
Does this guarantee approval?: No. DTI is one factor. Credit, assets, LTV, employment history, and program rules also matter.
How do deferred student loans count?: Some lenders use a percent of the balance (e.g., 0.5–1%) if no payment is reported. This tool uses your entered payment—enter a conservative estimate if deferred.
What about joint borrowers?: Combine gross incomes and all debts for both borrowers to get a household DTI. Lenders usually assess combined DTI for co-borrowers.
Do utilities or childcare count?: Typically not in DTI, but they matter for your real budget. Include them separately when assessing affordability.

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Illustrative DTI tool. Real underwriting may impute student loan payments, adjust self-employed income, or require different caps. It does not factor credit, assets, reserves, LTV, or property-specific conditions. Include full PITI/HOA and known debts for a closer estimate, and verify program specifics with your lender. Not financial advice.