Interactive explainer
How the House Affordability works
Use this explainer to understand how income, existing debt, down payment, rates, and escrow costs combine into a conservative home price.
Live explainer
Adjust the assumptions
Change inputs here to see the same calculation logic update immediately.
Enter gross yearly income before taxes.
Include car loans, student loans, credit cards, and other required payments.
Enter the cash you can put toward the purchase upfront.
Use the expected annual mortgage interest rate.
Enter the mortgage repayment period in years.
Estimate monthly property tax, homeowners insurance, and similar escrow costs.
Immediate results
Max Home Price
$256,221.45
Max Housing Payment
$1,866.67
Max Loan Amount
$216,221.45
Sensitivity analysis
Existing debts and interest rate can reduce buying power quickly because both affect the lender-style payment ceiling.
| Input | Scenario | Input value | Output | Output value |
|---|---|---|---|---|
| Annual Income | -10% | $72,000.00 | Max Home Price | $223,524.55 |
| Annual Income | Current | $80,000.00 | Max Home Price | $256,221.45 |
| Annual Income | +10% | $88,000.00 | Max Home Price | $285,754.14 |
| Monthly Debts | -10% | $450.00 | Max Home Price | $256,221.45 |
| Monthly Debts | Current | $500.00 | Max Home Price | $256,221.45 |
| Monthly Debts | +10% | $550.00 | Max Home Price | $253,584.61 |
| Down Payment | -10% | $36,000.00 | Max Home Price | $252,221.45 |
| Down Payment | Current | $40,000.00 | Max Home Price | $256,221.45 |
| Down Payment | +10% | $44,000.00 | Max Home Price | $260,221.45 |
| Interest Rate | -10% | 5.85% | Max Home Price | $271,661.61 |
| Interest Rate | Current | 6.5% | Max Home Price | $256,221.45 |
| Interest Rate | +10% | 7.15% | Max Home Price | $242,347.20 |
| Loan Term | -10% | 27 Years | Max Home Price | $248,474.76 |
| Loan Term | Current | 30 Years | Max Home Price | $256,221.45 |
| Loan Term | +10% | 33 Years | Max Home Price | $262,599.05 |
| Taxes & Insurance | -10% | 450 $/mo | Max Home Price | $264,131.99 |
| Taxes & Insurance | Current | 500 $/mo | Max Home Price | $256,221.45 |
| Taxes & Insurance | +10% | 550 $/mo | Max Home Price | $248,310.91 |
Formula and calculation model
This calculator applies the **28/36 Rule**, a standard used by mortgage lenders: 1. **Front-End Ratio (28%)**: Your monthly housing costs (Mortgage + Tax + Insurance) should not exceed 28% of your gross monthly income. 2. **Back-End Ratio (36%)**: Your total monthly debt payments (Housing + Cars + Loans) should not exceed 36% of your gross monthly income. The calculator finds the maximum loan amount that satisfies *both* rules.
Input definitions
Annual Income
Your total gross household income before taxes. Include salary, bonuses, and other reliable income sources.
Monthly Debts
The sum of your minimum monthly payments for credit cards, auto loans, student loans, and other personal debts.
Down Payment
The amount of cash you have saved to pay upfront. A larger down payment reduces the loan amount and increases your price range.
Interest Rate
Use the expected annual mortgage interest rate.
Loan Term
Enter the mortgage repayment period in years.
Taxes & Insurance
Estimate monthly property tax, homeowners insurance, and similar escrow costs.
What the results mean
Max home price
The modeled purchase price that fits the limiting debt-ratio rule.
Max housing payment
The estimated monthly housing ceiling before the loan amount is derived.
Common mistakes
Using take-home pay instead of gross income
Lender ratios usually start with gross income.
Enter annual gross income for this lender-style estimate.
Forgetting non-housing debts
Car, student loan, and credit card payments reduce borrowing capacity.
Include required monthly debts before trusting the price range.
Scenario and industry examples
Scenario
Conservative buyer
Moderate debts and standard housing ratio limits.
Scenario
Debt-constrained buyer
Higher monthly debt limits the safe housing payment.
Residential mortgage
Pre-approval prep
A buyer tests whether paying off a car loan changes their price range.
Real estate
Listing search
An agent helps a buyer narrow listings to a sustainable monthly payment.
Glossary
- PITI
- Principal, Interest, Taxes, and Insurance. The components of a monthly mortgage payment.
- DTI
- Debt-to-Income Ratio. The percentage of your gross monthly income that goes to paying debts.
- Front-End Ratio
- The percentage of income that goes toward housing costs.
FAQ clusters
Affordability planning
Should I use this result as a loan approval?
No. Use it as a planning estimate, then verify eligibility, rates, reserves, and program rules with a lender.
Why do small input changes move the result so much?
Housing and loan calculators compound assumptions across interest, term, principal, and recurring costs, so rate or debt changes can have a large monthly effect.