Mortgage Affordability Calculator
Find out how much house you can afford based on your gross income, existing monthly debts, down payment, and current interest rates — using the standard 28/36 lending rule.
Car payments, student loans, credit cards, etc.
The 28/36 Rule Explained
Most conventional mortgage lenders use the 28/36 rule to determine how much you can borrow:
- 28% front-end ratio — Your monthly housing payment (P&I + taxes + insurance) should not exceed 28% of your gross monthly income
- 36% back-end ratio — Your total monthly debt payments (housing + all other debts) should not exceed 36% of your gross monthly income
This calculator uses the 28/36 rule to find the maximum monthly mortgage payment you qualify for, then works backwards to the maximum home price.
What Counts as Monthly Debt?
Include all minimum monthly debt payments:
- Car loans
- Student loan minimum payments
- Credit card minimum payments
- Personal loans
- Any other installment or revolving debt
Do not include utilities, subscriptions, groceries, or expenses that are not formal debt obligations.
Why the Conservative Estimate?
The maximum the bank will lend you is not necessarily what you should borrow. The conservative estimate (80% of maximum) gives you more breathing room for unexpected expenses, repairs, job changes, or rising property taxes and insurance. Many financial advisors suggest keeping housing costs at or below 25% of take-home pay.
Frequently Asked Questions
Does this match what a lender will actually approve?
It closely follows standard conventional loan guidelines. FHA loans allow up to 43% back-end DTI. Some lenders go to 45–50% with strong compensating factors like excellent credit or large reserves. Use this as a starting point before meeting with a lender.
Should I enter gross or net income?
Lenders use gross income (before taxes). Enter your annual gross salary or combined household gross income if buying with a partner.
What about property taxes and insurance?
This calculator finds the max P&I payment and home price. Your actual monthly outlay will be higher once you add property taxes (~1–1.5% of home value/year) and homeowner's insurance (~0.5–1%/year).
