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Debt-to-income calculator

Calculate front-end and back-end debt-to-income ratios from gross income, housing payment, and other monthly debt obligations. See how lenders may view your borrowing capacity before you apply for a mortgage or other loan.

How this calculator works

This calculator computes two debt-to-income ratios from gross income and monthly obligations. Enter gross annual household income, monthly housing payment, and other monthly debt payments. The calculator converts annual income to gross monthly income, then divides housing payment by income for front-end DTI and total debt payments by income for back-end DTI.

Front-end DTI isolates housing costs—rent or full mortgage payment including taxes and insurance. Back-end DTI adds other recurring debt minimums such as car loans, student loans, and credit cards. Results include both ratios, gross monthly income, and total monthly debt payments for context.

Lenders commonly evaluate back-end DTI when underwriting mortgages because it reflects your full monthly obligation load. Front-end DTI helps assess whether housing alone consumes too much income even before other debts. This tool uses the same ratio math lenders apply at a high level; it does not replicate every program-specific rule.

The output is a snapshot based on inputs you provide today. It does not project future income, upcoming debt payoffs, or proposed mortgage payment unless you enter those values manually.

What affects the result

Three inputs determine both ratios. Because DTI is a percentage, the same dollar change has a larger impact on lower incomes.

  • Gross annual income is household income before taxes. Higher income lowers DTI for the same debt payments. Use documented gross wages, salary, and predictable income lenders would count—not net take-home pay.
  • Monthly housing payment is rent or full housing cost for owners and buyers. Include principal, interest, taxes, insurance, HOA, and PMI when relevant. Underestimating housing inflates affordability on paper.
  • Other monthly debt payments are minimum required payments on non-housing debts. Include auto loans, student loans, personal loans, credit card minimums, and obligations like child support. Exclude utilities and discretionary spending.

A $200 increase in total monthly debts on $6,000 gross monthly income raises back-end DTI by roughly 3.3 percentage points. Paying off a $350 car payment removes that entire slice from back-end DTI.

Real-world examples

  1. Renter preparing to buy. Income $96,000 ($8,000/month gross), rent $2,200, other debts $650. Back-end DTI is 35.6%—within many lender guidelines. Front-end is 27.5%, near the common 28% housing benchmark.

  2. Homeowner with car and student loans. Same income, mortgage $2,800, other debts $900. Back-end DTI rises to 46.3%, which may challenge conventional approval without paying down debts or increasing income.

  3. Dual-income household. Combined income $140,000, housing $2,400, other debts $500. Back-end DTI near 24.9% leaves room for a larger mortgage payment if other qualifications align—use the home affordability calculator to translate that capacity into price.

  4. Single debt payoff before applying. Reducing other debts from $650 to $300 by paying off a credit card drops back-end DTI by 4.4 points on $8,000 monthly income—sometimes enough to cross a lender threshold.

Common mistakes

  • Using net instead of gross income. Lenders underwrite on gross pay; net income makes DTI look worse than lenders calculate.
  • Omitting minimum credit card payments. Even small minimums count in back-end DTI.
  • Entering proposed mortgage payment while still renting. Use current rent for today's DTI; use estimated full housing payment when modeling a purchase scenario.
  • Excluding co-borrower income or debts. Household DTI typically includes all borrowers on the application.
  • Treating DTI below 43% as automatic approval. Credit, reserves, and employment history still matter.
  • Ignoring debts about to be paid off. If a loan closes within months, confirm with your lender whether it can be excluded from DTI.

When to use this calculator

Use this calculator before applying for a mortgage, HELOC, or other large loan to see where your ratios stand. Pair it with the home affordability calculator when converting DTI capacity into a price range, and with the loan payment calculator to estimate how a listing's payment affects back-end DTI.

Run it after paying down revolving debt or before taking on new obligations such as a car loan. Revisit when income changes materially. For deeper context on front-end vs. back-end limits and the 28/36 rule, see the how much house can I afford guide and debt-to-income explained guide.

Frequently asked questions

What is a good debt-to-income ratio for a mortgage? Conventional lenders generally look for a back-end DTI below 43%. Many prefer 36% or lower, and some programs require 45% or less for borrowers with strong compensating factors. The front-end (housing-only) guideline is commonly 28%. FHA loans allow higher DTI with a minimum credit score, while jumbo loans are often stricter. DTI is one qualification factor among several — credit score, down payment, and reserves also matter.

Does DTI affect my interest rate? DTI primarily determines whether you qualify, not the rate you receive. Mortgage rates are priced mainly through credit score and loan-to-value ratio. However, a very high DTI may restrict you to specific loan programs with their own pricing. Lowering DTI before application can expand which programs and lenders are available, which indirectly affects the rates you can access.

Should I use pre-tax or post-tax income? Always use gross (pre-tax) income. Mortgage underwriters calculate DTI exclusively on documented gross income — wages, salary, and qualifying predictable income before any deductions. Entering your net take-home pay will make your DTI appear significantly higher than what lenders actually calculate, which could lead you to incorrectly assume you cannot qualify.

What debts count in back-end DTI? Include minimum required monthly payments on installment loans (auto, student, personal), revolving credit cards, lines of credit, and legal obligations like child or spousal support. Do not include utility bills, cell phone payments, gym memberships, subscriptions, or discretionary spending. Lenders pull payment obligations from your credit report, so only debts appearing there are typically counted.

How do I improve my DTI before applying for a mortgage? Two levers move DTI: increase documented gross income or reduce monthly debt obligations. Paying off installment loans eliminates their minimum payment from back-end DTI entirely. Paying down revolving balances may reduce required minimums even if the account stays open. Avoid taking on new debt — auto loans, personal loans, or new credit card spending — in the months before applying. For a detailed buying timeline and qualification checklist, see the buying a home guide and the home affordability calculator.

Can I include rental income or freelance income? Lenders can count rental income and self-employment income, but they typically require two years of documented history and may apply a discount. Rental income usually requires Schedule E tax documentation. Freelance or contract income requires two years of returns showing consistent earnings. Enter only income your lender will count — not what you expect to earn in the future.

What is the difference between front-end and back-end DTI for lenders? Front-end DTI covers housing costs only — principal, interest, taxes, insurance, HOA, and PMI. Back-end DTI adds all other recurring monthly debt obligations on top of housing. Lenders typically look at both: the front-end ratio tests whether your housing cost alone is reasonable relative to income, while back-end DTI tests your total monthly debt load. Some loan programs have separate guidelines for each — for example, a program may allow 28% front-end and 36% back-end DTI as targets. Exceeding either limit can affect approval even if the other ratio is comfortable.

Related calculators

Check affordable price ranges based on income, DTI, and down payment with the home affordability calculator. Estimate mortgage principal and interest for a specific purchase with the loan payment calculator. Compare the total cost of renting versus buying over time with the rent vs. buy calculator. Model personal loan payments and how they add to monthly obligations with the personal loan calculator. See how extra mortgage payments affect payoff timeline with the extra mortgage payment calculator.

FAQ

What is debt-to-income ratio?

Debt-to-income (DTI) compares monthly debt payments with gross monthly income. Front-end DTI includes housing costs only. Back-end DTI adds housing to other recurring debt payments such as car loans, student loans, and credit card minimums. Lenders use these ratios to judge whether your income supports new borrowing alongside existing obligations.

What is the difference between front-end and back-end DTI?

Front-end DTI divides housing payment by gross monthly income. Back-end DTI divides total monthly debt payments—including housing—by gross monthly income. Mortgage lenders often focus on back-end DTI because it captures your full debt load, though some programs also track front-end housing costs separately.

What DTI do lenders typically want?

Many conventional lenders prefer back-end DTI at or below 36% to 43%, though program limits vary. FHA and other government-backed loans may allow higher ratios with compensating factors such as strong credit or reserves. Use this calculator for planning; pre-approval confirms what a specific lender will accept.

Should I use gross or net income?

Lenders generally use gross income—the amount before taxes and payroll deductions—when calculating DTI for mortgage applications. Enter annual gross household income here. Net take-home pay is useful for budgeting but does not match how most lenders underwrite loans.

What counts as a housing payment?

For renters, use your monthly rent. For homeowners or buyers, use the full monthly housing cost including principal, interest, property taxes, homeowners insurance, HOA dues, and PMI if applicable. Match the payment you would report on a mortgage application or the rent you actually pay today.

Which debts should I include in other monthly payments?

Include minimum monthly payments on car loans, student loans, personal loans, credit cards, child support, alimony, and other obligations lenders typically count. Exclude utilities, groceries, insurance not counted in DTI, and discretionary spending. When unsure, use what you would disclose on a loan application.

Does this guarantee mortgage approval?

No. Lenders also evaluate credit scores, employment history, assets, reserves, property type, and loan program rules. Self-employed borrowers may face additional documentation. A DTI within common guidelines is helpful but not sufficient on its own for approval.

How is this different from the home affordability calculator?

This calculator shows your current DTI from income and payments you enter. The home affordability calculator works backward from income and debts to estimate an affordable home price at different DTI targets. Use both when planning a purchase: affordability for price range, DTI for where you stand today.

Can I improve my DTI before applying?

Paying down revolving balances, avoiding new debt, increasing documented income, or adding a co-borrower can lower DTI. Paying off a car loan removes that minimum payment entirely. Even small reductions in monthly obligations can shift back-end DTI meaningfully on moderate incomes.

Why might my lender's DTI differ from this result?

Lenders may treat certain debts differently, use verified income instead of stated amounts, or include proposed housing payment rather than current rent. Some programs exclude specific obligations. Treat this output as a planning estimate and confirm numbers during pre-qualification or pre-approval.