House Affordability Calculator
Estimate the maximum home price you can afford using the 28/36 debt-to-income rule, based on income, debts, down payment, rate, and loan term.
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Max Affordable Home Price
$372,243
Max Loan Amount
$332,243
Max Monthly Payment
$2,100
How Home Affordability Is Calculated
This calculator uses the classic 28/36 debt-to-income guideline: no more than 28% of gross monthly income should go to housing costs (the "front-end" ratio), and no more than 36% should go to total debt payments including housing (the "back-end" ratio). Both ratios are adjustable so you can match a specific lender's guidelines. The stricter of the two limits sets your maximum affordable monthly payment, which is then converted into a maximum loan amount and home price.
Back-End Limit = (Monthly Income × Back Ratio %) − Other Monthly Debts
Max Home Price = Loan Amount (from max payment) + Down Payment
Example
With a $90,000 annual income, $400 in other monthly debts, a $40,000 down payment, a 6.5% interest rate, and a 30-year loan, the 28% front-end limit allows about $2,100/month for housing, while the 36% back-end limit (after debts) allows about $2,300/month — so the front-end ratio is the binding constraint. That translates into a maximum affordable home price in the mid-$300,000s.
Common Use Cases
- Getting a realistic home price range before house hunting.
- Understanding how existing debts reduce your home-buying budget.
- Testing how a bigger down payment or lower rate changes affordability.
- Preparing for a mortgage pre-approval conversation with a lender.
FAQs
What is the 28/36 rule?
It's a widely used lending guideline: housing costs shouldn't exceed 28% of gross monthly income, and total debt payments (housing plus other debts like car loans and credit cards) shouldn't exceed 36%. Some lenders allow higher ratios depending on credit and loan type.
Why did adjusting my other debts change the result?
The back-end ratio limit accounts for all monthly debt obligations, not just housing. Higher existing debts (car payments, student loans, credit cards) reduce how much room is left for a mortgage payment under the 36% ceiling.
Does this include property taxes and insurance?
This estimate focuses on principal and interest capacity based on the debt-to-income ratios. Actual affordability should also factor in property taxes, homeowners insurance, and HOA fees, which lenders typically fold into the front-end ratio calculation.