How much house can your income support? Get a maximum purchase price, full monthly payment breakdown, and DTI analysis.
About this calculator
This calculator uses standard debt-to-income (DTI) guidelines (the same ratios lenders use) to estimate the maximum home price your income and debt load can support. The front-end DTI (housing costs only) is capped at 28% of gross monthly income; the back-end DTI (housing plus all other monthly debts) is capped at 43%. The more restrictive of the two constraints determines your maximum purchase price. Monthly costs include principal & interest, property tax, homeowner's insurance, PMI (if your down payment is below 20%), and any HOA dues.
Not financial advice. This tool uses standard guidelines as a starting point. Actual loan approval depends on your credit score, employment history, reserve requirements, loan type, and lender-specific overlays. Consult a licensed mortgage professional before making decisions.
Your Finances
Income and existing monthly debt obligations
$
Combined gross household income for all borrowers
$
Car loans, student loans, credit card minimums (not the future mortgage)
Loan Details
Down payment, rate, and term
$
Cash toward the purchase; a higher down payment raises your maximum price
%
3%12%
Use the interest rate, not APR
$
Annual rate as % of home value; varies widely by location
$
Annual insurance premium as % of home value
$
Monthly HOA dues (leave blank if none)
$
Annual PMI as % of loan; applies only if down payment < 20%
Affordability Analysis
Results update instantly as you adjust inputs
MAX PURCHASE PRICE
—
at DTI limit
TOTAL MONTHLY PAYMENT
—
PITI + HOA
FRONT-END DTI
—
28% guideline
BACK-END DTI
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43% guideline
ℹ
Enter your income and finances above
The calculator will show your maximum purchase price and monthly payment breakdown based on standard lending DTI guidelines.
MONTHLY PAYMENT BREAKDOWN
Principal & Interest—
Property Tax—
Homeowner's Insurance—
PMI (if <20% down)—
HOA Dues—
Total Monthly—
DEBT-TO-INCOME RATIOS
Front-end DTI (housing only)—
28% conventional guideline
Back-end DTI (all debts)—
43% conventional guideline
RATE SENSITIVITY: HOW RATE CHANGES AFFECT YOUR MAX PRICE
Rate
Max Purchase Price
Monthly Payment
Enter your income above to see rate sensitivity.
How It Works & Key Concepts
DTI limits, what counts toward housing costs, and what the calculator doesn't model
DTI Guidelines
Front-End DTI (28%)
The front-end ratio (also called the housing ratio) measures total monthly housing costs (principal, interest, property tax, insurance, PMI, and HOA) as a percentage of gross monthly income. Conventional lenders typically cap this at 28%. FHA loans allow up to 31%. This ratio prevents the mortgage alone from consuming too large a share of income, leaving no room for other obligations.
Back-End DTI (43%)
The back-end ratio measures total monthly debt obligations (housing costs plus all other recurring debt payments: car loans, student loans, credit card minimums, personal loans) as a percentage of gross monthly income. The conventional limit is 43%; some loan programs allow up to 50% with compensating factors. This is typically the binding constraint for borrowers carrying significant non-housing debt. If your back-end ratio is close to the limit, paying off other debts before applying can significantly increase your buying power.
Which Constraint Binds?
This calculator solves for the maximum purchase price that satisfies both DTI limits and uses whichever is more restrictive. For borrowers with little non-housing debt, the front-end ratio (28%) typically binds first. For borrowers with car loans, student debt, or other obligations, the back-end ratio (43%) often determines the ceiling. The binding constraint is shown in the analysis; reducing the binding debt type will have the biggest effect on your buying power.
The Math Behind the Number
The calculator solves for a purchase price P such that total monthly housing costs equal the maximum permitted by the more restrictive DTI. Because monthly costs include both loan-dependent items (P&I, PMI) and price-dependent items (property tax, insurance), the solution requires solving a simple linear equation. PMI is handled by checking whether a 20% down payment is achievable at the no-PMI solution; if not, the PMI-adjusted formula is used instead.
What This Calculator Doesn't Model
Credit Score Impact
DTI limits are just one component of loan approval. Credit score has an equal or greater impact on whether you qualify and what rate you receive. A score below 620 typically disqualifies conventional financing; below 740, you'll pay a higher rate. A borrower with a 780 score and 41% back-end DTI may qualify easily; one with a 640 score and 38% back-end DTI may face denial. This calculator cannot model credit score effects — get a pre-approval to understand your actual rate.
Loan Type Variations
Different loan types carry different DTI limits. FHA loans allow front-end DTI up to 31% and back-end up to 43–50% (with compensating factors). VA loans for eligible veterans have no hard DTI limit but use a residual income test. USDA rural loans cap at 41% back-end. Jumbo loans (above conforming limits) typically require lower DTIs (often 36–38% back-end) and larger down payments. This calculator uses conventional conforming guidelines as a baseline.
Reserves and Cash-to-Close
Lenders require cash not just for the down payment but for closing costs (typically 2–5% of the purchase price), prepaid items (homeowner's insurance upfront, property tax escrow), and post-closing reserves (often 2–6 months of PITI). Many borrowers who technically qualify on DTI are limited in practice by available cash. A $500,000 home might require $25,000 down plus $15,000–$20,000 in closing costs and reserves, for a total of $40,000–$45,000 cash to close.
True Cost of Ownership
What you can borrow and what you can comfortably afford are different questions. This calculator shows the maximum lenders will approve — it says nothing about maintenance (budget 1–2% of home value annually), capital improvements, or the risk of income disruption. A payment at 28% of gross income may feel tight once you account for taxes, retirement contributions, healthcare, and lifestyle. Many financial planners suggest targeting 25% or less of gross income for housing costs rather than the 28% ceiling lenders use.