Mortgage qualifying ratios, without pretending to approve the loan.
Build true PITI, expand it into qualifying housing expense, itemize recurring debt, calculate both ratios, and see which entered limit controls the scenario.
Housing ratio = qualifying housing expense / gross monthly income. Total DTI adds the applicable recurring monthly obligations before dividing by gross monthly income. Use the limits supplied by the question or program, and keep the result separate from a real underwriting decision.
Keep mortgage insurance, HOA dues, and other required housing obligations visible on separate lines.
Divide qualifying monthly housing expense by gross monthly income before taxes and deductions.
Add the applicable recurring monthly obligations before dividing by gross monthly income.
Calculate income under each entered limit. The larger requirement is the controlling scenario constraint.
Compare the housing amount allowed by the housing limit with the amount left under the total-DTI limit.
28/36 is a familiar classroom setup, not a universal product rule or approval standard.
Build the housing expense, then add every monthly obligation.
Use the information in the question. Do not recalculate P&I when the stem already gives it.
Choose the final ask before building the ratio numerator and denominator.
Enter the P&I amount supplied in the exam stem or scenario.
Classic PITI stops after property taxes and homeowners insurance. Enter applicable mortgage insurance, HOA dues, and other required housing obligations on their own lines.
Enter PMI, MIP, or another required monthly mortgage-insurance amount when stated.
Use when the facts require flood insurance, ground rent, special assessments, subordinate financing, or another housing obligation.
Enter the monthly payment required by the question or applicable rule, not the account balance. Actual underwriting decides which obligations count and how each payment is documented.
Use for stated alimony, child support, maintenance, or lease payments when applicable.
Ratios use gross income before taxes and deductions. The calculator converts annual income to a monthly amount.
Scenario input only. Use the limit supplied by the question or program.
Scenario input only. Different programs and underwriting methods use different rules.
Classic PITI is $2,520.00. The broader qualifying housing expense is $2,520.00 after stated mortgage insurance, HOA, and other housing obligations.
Total DTI uses $3,240.00 of monthly obligations, including $720.00 outside the subject housing expense.
$9,000.00 gross monthly income is used before taxes and payroll deductions. Monthly obligations stay paired with monthly income.
The 28% and 36% limits are user-entered scenario assumptions. The result is not a prequalification, approval, or statement of current product eligibility.
$2,000.00 monthly P&I was entered directly from the scenario.
Calculations keep full precision. Displayed money is rounded to cents and ratios to two decimal places. Actual underwriting may use different qualifying payments, income treatment, debt-payment rules, tolerances, automated underwriting, compensating factors, and product limits.
Email the full qualifying-ratio proof.
Keep true PITI, qualifying housing, itemized debt, both ratios, entered limits, and required income together.
Try five qualifying-ratio traps without the calculator.
Qualifying housing expense is $2,520 and gross monthly income is $9,000. What is the housing expense-to-income ratio?
Five totals that should never be blurred together.
The fastest way to catch a ratio error is to label the numerator and denominator before dividing.
| Total | What it includes | Where it is used |
|---|---|---|
| Classic PITI | Principal, interest, property taxes, homeowners insurance | Base mortgage and escrow math |
| Qualifying housing expense | PITI plus applicable mortgage insurance, HOA, and other required housing obligations | Housing-ratio numerator |
| Other monthly debt | Applicable installment, revolving, student-loan, lease, support, and other obligations | Added for total DTI |
| Total monthly obligations | Qualifying housing expense plus other monthly debt | Total-DTI numerator |
| Gross monthly income | Qualifying income before taxes and deductions | Denominator for both ratios |
Build each line before testing a limit.
Good qualifying math is mostly disciplined classification.
Name the requested ratio
Housing expense-to-income and total DTI use different numerators. Mark the exact answer before choosing amounts.
Find monthly P&I
Use P&I supplied in the stem, calculate a fixed-rate payment, or multiply the loan in thousands by the supplied factor.
Build qualifying housing
Start with classic PITI, then add the mortgage insurance, association dues, and other required housing obligations stated in the facts.
Add applicable monthly debts
Use monthly payments, not account balances. Actual product rules determine which obligations count and how their payments are calculated.
Match the time period
Divide annual gross income by 12 before comparing it with monthly housing expense and monthly debt payments.
Treat limits as scenario inputs
Use the limits supplied in the question or selected program. A ratio result alone is not mortgage approval.
Six patterns, each with a different lesson.
Every example matches a calculator preset so students can reproduce it instantly.
$2,000 P&I, $400 tax, $120 home insurance, $720 other debt, $9,000 income
This is a clean classroom pattern, not a promise that every lender uses 28/36.
$400,000 price, 20% down, 6.75%, 30 years
At entered 28/36 limits, the housing side controls and requires about $9,483.98 monthly income.
$2,520 housing, $900 other debt, $9,000 income
The housing ratio is unchanged, but the added debts make the total-DTI limit controlling.
$240,000 loan, factor 6.49, $550 taxes and home insurance
Do not apply a per-$1,000 factor to the whole loan amount.
$2,655.51 PITI, $150 mortgage insurance, $225 HOA
Classic PITI stays visible even though the qualifying housing numerator is broader.
$108,000 gross annual income
Never divide monthly obligations by annual income.
Six ways this calculator stays honest.
PITI is not every qualifying housing cost
Mortgage insurance, association dues, flood insurance, ground rent, special assessments, and secondary financing can matter without changing what the letters PITI mean.
Housing ratio and total DTI are different
The housing ratio uses qualifying housing expense. Total DTI adds the applicable recurring monthly obligations.
Use qualifying gross monthly income
Gross income is measured before taxes and deductions. Annual income must be converted to the same monthly period as the obligations.
A balance is not automatically the monthly payment
Installment, revolving, student-loan, lease, and support obligations can follow product-specific payment and remaining-term rules.
There is no universal qualifying-ratio pair
Loan program, underwriting method, compensating factors, credit, reserves, and current policy can change the applicable limit or evaluation.
Ratio math is not underwriting
A lender also verifies income, assets, employment, credit history, loan terms, property data, and monthly obligations under current rules.
Current sources behind the formulas and guardrails.
The product guides are included to explain why housing items, debt treatment, and ratio limits cannot be reduced to one universal rule.
Connect qualification to the rest of the financing question.
Mortgage qualifying-ratio FAQ.
What is the housing expense-to-income ratio?+
It is qualifying monthly housing expense divided by gross monthly income. It is often called a housing ratio or front-end ratio. The exact housing items and applicable limit depend on the question or loan program.
What is the back-end or total debt-to-income ratio?+
It is total monthly obligations divided by gross monthly income. The numerator starts with qualifying housing expense and adds the recurring monthly debts that apply under the stated rules.
Are PITI and qualifying housing expense the same?+
Not always. Classic PITI is principal, interest, property taxes, and homeowners insurance. A qualifying housing expense can also include mortgage insurance, HOA or association dues, flood insurance, ground rent, special assessments, subordinate financing, or other required amounts when applicable.
Are 28% and 36% the current universal mortgage limits?+
No. They are familiar classroom and traditional underwriting reference points. Current limits and evaluation methods vary by loan program, manual or automated underwriting, credit, reserves, compensating factors, lender overlays, and other rules. Use the limits stated in the question or actual program guidance.
Which income belongs in a qualifying ratio?+
Use qualifying gross monthly income before taxes and payroll deductions. When annual income is supplied, divide it by 12. Actual underwriting also determines whether each income source is stable, documented, and eligible.
Which debts belong in total DTI?+
The scenario may include housing, installment payments, revolving payments, student loans, leases, alimony, child support, maintenance, and other recurring obligations. Actual programs have detailed rules for remaining terms, deferred debts, payoff, payment calculation, and exclusions, so follow the applicable guidance.
How does the calculator find required income?+
It divides qualifying housing expense by the entered housing-limit decimal, then divides total monthly obligations by the entered total-DTI-limit decimal. The higher income is required to satisfy both entered constraints in that scenario.
Why might a lender calculate a different DTI?+
A lender may use a different qualifying mortgage payment, verified income amount, debt payment, property charge, program limit, automated underwriting result, or current rule. The calculator cannot reproduce a full loan file or underwriting system.
Does this calculator prequalify or approve a borrower?+
No. It is an educational scenario tool for Texas real estate exam preparation. Only an authorized lender applying current program requirements to verified borrower and property information can make a lending decision.