House Affordability CalculatorFree online financial calculator — instant results, no sign-up
Find a home price that fits your income and debts (28/36 rule).
Estimates only, based on the inputs and assumptions shown. This is not financial, investment, tax, or legal advice. Prices, rates and local rules may change; crypto scenarios do not predict returns. Confirm important decisions with a qualified professional.
Sign in to save results and favorites.
About the House Affordability Calculator
This calculator estimates the maximum home purchase price and mortgage amount you can afford based on the standard 28/36 debt-to-income rule. It determines your allowable monthly housing payment using your gross income and recurring debts, then factors in your down payment, interest rate, loan term, and ongoing property taxes and insurance. Homebuyers can use it to set a realistic budget before shopping for properties or applying for pre-approval.
- Annual income
- Gross pre-tax yearly income from all borrowers, in dollars; typically $20,000 to $500,000+.
- Monthly debts
- Total monthly non-housing debt obligations like car loans, student loans, and credit card minimums, in dollars; typically $0 to $3,000.
- Down payment
- Cash available upfront toward the purchase price, in dollars; typically $0 to $200,000+.
- Interest rate
- Annual mortgage interest rate as a percentage; typically 3.0% to 10.0%.
- Term
- Mortgage repayment length in years; typically 15 or 30 years.
- Tax+insurance % of price / yr
- Combined estimated annual property tax and homeowners insurance rate as a percentage of home value; typically 1.0% to 2.5%.
Formula and method
mi = Annual Income / 12 maxPay = min(mi × 0.28, (mi × 0.36) − Monthly Debts) unit = (r / 12) / (1 − (1 + r / 12)^(-12 × Years)) Affordable Home Price = (maxPay + Down Payment × unit) / (unit + (Tax & Insurance Rate / 1200)) Loan Amount = Affordable Home Price − Down Payment
- miGross monthly income
- maxPayMaximum allowable monthly housing budget under the 28/36 rule
- unitMonthly mortgage payment per dollar of loan principal
- rAnnual mortgage interest rate expressed as a decimal (e.g., 0.065 for 6.5%)
The tool evaluates both the front-end cap (28% of monthly income) and back-end cap (36% of monthly income minus existing debts) to establish your maximum monthly housing budget as the lesser of the two. It then solves the linear payment equation where monthly principal, interest, taxes, and insurance equal that maximum payment budget. The final output rounds the home price, loan balance, and payment to standard currency amounts.
Worked example
These are the calculator's starting values and the results it actually produces for them.
Inputs
- Annual income100000 $
- Monthly debts500 $
- Down payment60000 $
- Interest rate6.5 %
- Term30 years
- Tax+insurance % of price / yr1.5 %
Results
- Affordable home price$358,299.92
- Loan amount$298,299.92
- Max monthly housing$2,333.33
How to use the House Affordability Calculator
- 1Divide annual income by 12 to find monthly gross income, then calculate 28% of gross income and 36% minus existing monthly debts.
- 2Select the smaller of those two figures as the maximum monthly housing payment.
- 3Calculate the monthly mortgage payment factor per dollar of borrowed principal using standard amortization over the chosen loan term.
- 4Solve for home price by balancing the maximum monthly payment against loan repayment, down payment credit, and monthly tax and insurance costs.
Reading your result
The Affordable Home Price indicates the highest purchase price that keeps your total housing costs within the stricter of the 28% front-end or 36% back-end DTI limits. The Loan Amount reflects how much you will borrow after applying your down payment. The Max Monthly Housing figure represents your combined target ceiling for monthly principal, interest, property taxes, and homeowners insurance.
Limitations
This calculation does not account for private mortgage insurance (PMI) on down payments below 20%, homeowners association (HOA) fees, or one-time closing costs. It also applies fixed 28/36 DTI caps, whereas certain loan programs (like FHA, VA, or conventional conforming loans) may allow higher debt-to-income limits under strong credit profiles.
Common questions
What is the 28/36 rule?+
The 28/36 rule is a standard underwriting guideline where lenders prefer that no more than 28% of your gross monthly income goes toward housing costs (front-end DTI), and no more than 36% goes toward all recurring debts combined (back-end DTI).
Why does having monthly debt lower my home price ceiling?+
When monthly non-housing debts are high, the 36% back-end limit leaves less money available for housing, reducing your maximum monthly housing payment and the loan amount you qualify for.
How does the annual tax and insurance percentage affect affordability?+
Property taxes and hazard insurance are billed alongside your mortgage payment; a higher percentage increases ongoing escrow costs, leaving less room for loan principal and lowering the total home price you can afford.
Does the calculator save my information?+
Calculations run in your browser. While signed in, inputs and results are automatically recorded in account history; saving a result creates a separate saved record.
Further reading
You might also like
Mortgage Calculator
Estimate your monthly house payment including taxes, insurance and HOA.
Amortization Calculator
See how each year of payments splits between interest and principal.
Mortgage Payoff Calculator
See how extra monthly payments shorten your loan and save interest.
Rent Calculator
How much rent you can afford based on income and debts.
Debt-to-Income Ratio Calculator
Measure your monthly debt payments against your gross income.
Real Estate Calculator
Return on a property purchase including appreciation and rent.
Results are estimates for informational purposes and are not financial, medical or legal advice.