The average American spends 30% of their income on housing, but financial advisors recommend keeping it under 28%. Lenders will often approve you for more than you can comfortably afford — that is the dangerous gap this calculator helps you avoid. By factoring in your gross income, existing debts, down payment, and current interest rates, it shows what you can realistically afford, not just what a bank will lend you. In 2026, with mortgage rates hovering between 6-7%, that distinction matters more than ever. A $100K household income qualifies for roughly $350K-$420K depending on debts, but comfortable affordability often lands closer to $300K when you account for property taxes, insurance, maintenance, and the lifestyle you want to maintain.
Mortgage Affordability Calculator
How to Use This Calculator
- Enter your annual gross household income before taxes and deductions
- Add your total monthly debt payments — car loans, student loans, credit card minimums, and any other recurring obligations
- Set your expected down payment as a dollar amount or percentage of home price
- Adjust the interest rate to match current market rates — check Bankrate or Freddie Mac for today's average
- Review your maximum affordable home price and the recommended monthly payment breakdown
How It Works
This mortgage affordability calculator uses established formulas to provide accurate results.
The basic rule:
- 28% Rule: Monthly housing costs should not exceed 28% of gross monthly income
- 36% Rule: Total debt payments (housing + other) should not exceed 36% of gross income
- Monthly P&I = Loan × [r(1+r)^n] / [(1+r)^n − 1]
Real estate values and regulations vary significantly by location. Work with a local agent or attorney.
Tips & Considerations
- Lenders will approve you for more than you should spend. Qualifying for a $500K mortgage does not mean you can comfortably afford one — leave room for savings, emergencies, and life.
- Property taxes vary wildly by location. A $400K home in Texas costs $8K-$10K/year in property tax while the same home in Colorado might cost $2K-$3K. Factor this in.
- Do not forget closing costs — typically 2-5% of the home price. On a $400K home, that is $8K-$20K you need in addition to your down payment.
- Your debt-to-income ratio matters more than your credit score for determining how much you can borrow. Pay down existing debts before applying.
- Budget 1-2% of the home value annually for maintenance and repairs. A $400K home needs $4K-$8K per year set aside.
Frequently Asked Questions
How much house can I afford on a $100k salary?
On a $100,000 salary with no other debts, you can generally afford a home priced around $350,000-$420,000 depending on interest rates, down payment, and location. The 28% rule limits your total housing payment to about $2,333 per month. With a 20% down payment and a 6.5% rate on a 30-year mortgage, you could comfortably afford a $400,000 home.
What is the 28/36 rule?
The 28/36 rule is a widely used lending guideline. The front-end ratio (28%) says your total monthly housing costs — including mortgage principal, interest, property taxes, and insurance — should not exceed 28% of your gross monthly income. The back-end ratio (36%) says your total monthly debt payments (housing plus car loans, student loans, credit cards) should stay below 36% of gross income.
How much down payment do I need?
Conventional loans typically require 5-20% down. Putting 20% down avoids Private Mortgage Insurance (PMI), which costs 0.5-1% of the loan annually. FHA loans allow as little as 3.5% down, and VA loans offer 0% down for eligible veterans. A larger down payment means a smaller loan, lower monthly payments, and often a better interest rate.
What is DTI and why does it matter?
Debt-to-income ratio (DTI) measures the percentage of your gross monthly income that goes toward debt payments. Most conventional lenders want a DTI below 36%, though some will go to 43%. FHA loans may allow up to 50% in certain cases. A lower DTI not only makes qualifying easier but also means you have more financial breathing room for emergencies and other goals.
Should I get a 15-year or 30-year mortgage?
A 15-year mortgage has higher monthly payments but saves tens of thousands in interest and builds equity faster. The rate is typically 0.5-0.75% lower than a 30-year. A 30-year mortgage offers lower payments and more flexibility. If you can afford 15-year payments comfortably, it is usually the better financial choice — but do not stretch your budget so tight that you cannot save or handle emergencies.