Updated May 2026 · 28/36 Rule · No Email Required
Enter your gross income, monthly debts, and down payment — this calculator applies the 28/36 rule and live 2026 mortgage rates to show your maximum home price, monthly payment, and debt-to-income ratio in real time.
Estimates only. Actual qualification depends on credit score, lender, and local market conditions.
Other inputs (debts, down payment, rate, taxes) are pulled from the main calculator.
The higher of the two income requirements determines your minimum qualifying income.
Based on your income and debts from the main calculator, here is your maximum home price at different DTI thresholds. Rates, taxes, insurance, and down payment are unchanged.
| DTI Scenario | Front-End % | Max Housing Payment | Max Home Price | Monthly P&I |
|---|---|---|---|---|
| Switch to this tab to generate comparison | ||||
Assumes current rate, term, taxes, insurance, and HOA from the main calculator. Standard conventional at 28%/36%; FHA allows up to 31%/43%.
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The 28/36 rule is the standard used by Fannie Mae, Freddie Mac, and most conventional lenders to evaluate mortgage applications. It sets two limits on your monthly obligations relative to gross income — and your approval is determined by whichever limit is lower.
For a household earning $100,000/year ($8,333/month), the 28% front-end limit allows $2,333 in monthly housing costs. The 36% back-end limit allows $3,000 total — meaning if you already pay $700/month in car and student loans, only $2,300 is left for housing. In this case, the back-end rule becomes the binding constraint and reduces your max home price by roughly $40,000 compared to using the front-end rule alone.
Every DTI calculation uses pre-tax gross income, not your take-home amount. A buyer earning $80,000 gross might take home $58,000 after taxes. If they mistakenly apply the 28% rule to their take-home ($1,353/month), they'll underestimate their buying power significantly. Their lender calculates 28% of $6,667/month gross = $1,867 — a $514/month difference that translates to roughly $75,000 in additional home buying power at current rates.
A 1% change in your mortgage rate changes your buying power by roughly 10–11% on a 30-year loan. At 6.94%, a $2,000/month principal-and-interest budget supports a loan of about $300,000. At 7.94%, the same payment supports only $272,000 — an $28,000 reduction in loan capacity for every percentage point increase. This is why buyers who locked rates in 2020–2021 at 3% could afford homes that are effectively inaccessible at 2026 rates even with the same income.
Monthly debt obligations are subtracted directly from your back-end DTI capacity before housing is factored in. A $400/month car payment on a $90,000 income reduces maximum housing costs from $2,520 (36% limit) down to $2,120 — a $400/month reduction that translates to roughly $56,000 less in maximum loan amount at current rates. The calculator's individual debt inputs let you see exactly which obligations are eating into your home buying power and by how much.
Beyond reducing your loan balance, a larger down payment affects your monthly payment in two ways: a smaller loan means less P&I, and reaching 20% down eliminates PMI entirely. PMI typically costs 0.5–1.5% of the loan annually — on a $350,000 loan, that's $145–$437/month. Since PMI counts against your housing payment limit, eliminating it immediately improves your max loan amount. The PMI toggle in this calculator shows the exact impact on your home buying power.
The national average property tax rate is 1.1%, but individual markets vary enormously: New Jersey averages 2.4%, Illinois 2.2%, and Texas 1.8% — while Hawaii (0.3%), Alabama (0.4%), and Colorado (0.5%) are dramatically lower. On a $400,000 home, the difference between 0.5% and 2.0% property tax is $500/month — enough to shift your maximum home price by $70,000 or more. Always enter your local rate, not the national average.
This is the rule this calculator uses and the rule your lender will use. It's the most accurate estimate of what you'll actually qualify for. Use it when you want to know your real maximum mortgage qualification, not a conservative estimate or a quick back-of-envelope figure.
The Consumer Financial Protection Bureau's guidance for financially comfortable homeownership is to keep housing costs under 25% of net (after-tax) take-home pay. For a $100,000 gross income with ~28% effective tax rate, take-home is roughly $72,000/year ($6,000/month). Twenty-five percent of that is $1,500/month — substantially lower than the 28% gross income rule. This approach leaves more cash flow for savings, emergencies, and retirement contributions.
Multiply your gross annual income by 3 to get a rough home price estimate. For $100,000 income, that's a $300,000 home. This rule is simple but outdated — it was calibrated when mortgage rates were 6–7% and assumes 20% down. At 2026 rates with a 10% down payment, a more accurate multiplier is closer to 3.5–4× income for well-qualified buyers with low existing debt. The 3× rule is better used as a sanity check than a qualification estimate.
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Home affordability is calculated using the 28/36 rule. Your monthly housing costs (principal, interest, taxes, insurance) should not exceed 28% of gross monthly income, and your total monthly debts should not exceed 36%. To find your max home price, calculate your max monthly payment under both rules, take the lower figure, subtract estimated property taxes, insurance, and HOA fees, then use the remaining amount as your principal-and-interest payment in a reverse mortgage formula. Add your down payment to get your maximum home price. This calculator does all of this automatically the instant you enter your numbers.
A front-end DTI under 28% is considered good by conventional lenders — meaning housing costs are no more than 28% of gross monthly income. A back-end DTI under 36% (all debts combined) is considered excellent. Some FHA loans allow up to 43% back-end DTI, and certain jumbo lenders may go higher for strong borrowers. The CFPB recommends keeping housing costs under 25% of take-home pay for a comfortable financial cushion that leaves room for savings and emergencies.
On a $100,000 salary with no existing debts and a 20% down payment, you can typically afford a home priced between $380,000 and $440,000 depending on current interest rates. The 28% rule gives you a max monthly housing payment of about $2,333. At 6.94% on a 30-year mortgage, that supports a loan of roughly $348,000 — or a home around $435,000 with 20% down. If you carry $500/month in car or student loan payments, that home price drops by approximately $55,000–$70,000. See the full breakdown in our $100K salary affordability guide.
The 28/36 rule is the most widely used mortgage affordability guideline in the US. The "28" means monthly housing expenses (PITI — principal, interest, taxes, insurance) should not exceed 28% of gross monthly income. The "36" means all monthly debt obligations combined — including your new mortgage, car loans, student loans, and credit card minimums — should not exceed 36% of gross income. Lenders apply both and qualify you based on whichever limit is lower. For a household earning $7,000/month, that means max housing of $1,960 and max total debt of $2,520.
Minimum down payments vary by loan type: conventional loans start at 3%, FHA loans at 3.5%, VA and USDA loans at 0% for qualifying applicants. However, putting down less than 20% on a conventional loan triggers PMI (private mortgage insurance), which typically adds 0.5–1.5% of the loan balance annually to your monthly payment. The 2024 NAR survey puts the median first-time buyer down payment at 8%. Use our down payment calculator to see exactly how different amounts affect your monthly costs.
Yes — significantly. Your credit score determines your mortgage interest rate, which directly changes your monthly payment and maximum loan size. A borrower with a 760+ score might qualify at 6.44% while someone at 620 might get 7.44% for the same loan at current spreads. On a $350,000 loan over 30 years, that 1% rate difference adds about $225/month and $81,000 in total interest. Most conventional lenders require a minimum 620 score; FHA loans accept 580 with 3.5% down. Improving your score before applying can meaningfully expand your buying power.
Lenders count all recurring monthly debt obligations with required minimum payments: auto loans, student loan minimums, personal loans, credit card minimums, child support, and alimony. They do NOT count utilities, subscriptions, groceries, health insurance premiums, or retirement contributions. The average American carries about $1,700/month in non-mortgage debt (Federal Reserve data), which can reduce qualified home price by $80,000–$120,000 depending on income. The individual debt inputs in this calculator let you see the precise impact of each obligation.
Beyond principal and interest, budget for: property taxes (national avg 1.1% of value annually), homeowners insurance ($1,500–$2,500/year), PMI if putting less than 20% down (0.5–1.5% of loan per year), HOA fees (median $250/month in communities with HOAs), and closing costs (2–5% of purchase price). On top of that, plan for 1–2% of home value annually in maintenance — a $400,000 home may need $4,000–$8,000/year in repairs. Our first-time buyer calculator factors all of these into its total cost estimate.
Last updated: May 2026
This calculator applies the standard 28/36 rule used by conventional US mortgage lenders (Fannie Mae Selling Guide B3-6):
Front-End DTI = (Housing Costs / Gross Monthly Income) × 100 Back-End DTI = (All Monthly Debts / Gross Monthly Income) × 100 Binding Limit = min(Income × 0.28, Income × 0.36 − Monthly Debts) Max Monthly PI = Binding Limit − Monthly Tax − Monthly Insurance − HOA Max Loan = PI × [(1+r)ⁿ − 1] / [r × (1+r)ⁿ] Max Home Price = Max Loan + Down Payment
Where r = monthly interest rate (annual rate ÷ 12) and n = total payments (term in years × 12).
PMI estimated at 0.7% of loan annually when loan-to-value exceeds 80%.
Sources: CFPB Owning a Home · Fannie Mae B3-6-02 Debt-to-Income Ratios · Freddie Mac Seller/Servicer Guide · NAR 2024 Profile of Home Buyers and Sellers. Last reviewed May 2026.