Mortgage Affordability Calculator — How Much House Can You Afford?

Before a buyer falls in love with a property, they need to understand what they can actually afford. Our free mortgage affordability calculator gives buyers and their agents a clear, comprehensive picture — maximum home price, estimated monthly payment, full debt-to-income analysis, and a breakdown of every cost that goes into that monthly number.

How Much House Can You Afford?

The answer depends on four things: your income, your existing debts, your down payment, and the interest rate you qualify for. Lenders use a metric called the debt-to-income ratio (DTI) to determine how much of your gross monthly income can go toward housing costs and total debt obligations.

The 28/36 rule is the traditional guideline: no more than 28% of gross monthly income should go toward housing costs (principal, interest, taxes, and insurance), and no more than 36% toward total debt including car payments, student loans, and credit cards. FHA loans allow up to 43%, and some lenders will stretch to 50% for well-qualified borrowers.

How to Use This Calculator

1. Enter your gross annual income — add a co-borrower's income if buying jointly.
2. List existing monthly debt payments — car loans, student loans, and any other recurring obligations.
3. Set your down payment using the input or slider — the calculator shows your approximate down payment percentage as you adjust.
4. Set the interest rate using the slider — adjust to match current rates or what you've been quoted.
5. Choose loan term — 10, 15, 20, or 30 years.
6. Add property tax, home insurance, HOA fees — these are often overlooked but significantly affect the true monthly cost.
7. Select your DTI guideline — Conservative (28%), Standard (36%), FHA (43%), or Aggressive (50%).
8. Calculate — get your maximum home price, estimated monthly payment, a DTI affordability meter, a full payment breakdown with visual bar chart, a scenario table across seven price points, and an amortisation snapshot showing principal vs. interest over the life of the loan.

What's Really in Your Monthly Mortgage Payment?

Many first-time buyers focus on the principal and interest payment and overlook the full PITI — Principal, Interest, Taxes, and Insurance. In practice, lenders qualify buyers on the total housing payment, which includes all four.

Principal & Interest — the core loan repayment, which stays fixed for the life of a fixed-rate mortgage.

Property Tax — varies enormously by location, typically 0.5–2.5% of the home's assessed value annually.

Homeowners Insurance — typically $1,000–$2,500 per year for most homes.

HOA Fees — apply to condos and many planned communities, ranging from under $100 to over $1,000 per month.

PMI (Private Mortgage Insurance) — required on conventional loans when the down payment is less than 20%, typically costing 0.5–1% of the loan amount annually. The calculator flags this automatically.

Why Agents Should Use This Tool with Clients

Pre-qualifying conversations are more effective when buyers can see the numbers visually. Sharing this calculator at the first buyer consultation sets realistic expectations, focuses the property search on the right price range, and prevents the disappointment of falling in love with a home that's out of reach.

The scenario table shows buyers exactly what their monthly payment looks like across a range of price points — making trade-off conversations concrete and productive rather than abstract.

Manage Your Real Estate Business with Schemon

This calculator helps buyers understand what they can afford — Schemon helps agents manage the relationships, appointments, and payments that follow. One platform for scheduling, client communication, document sharing, and getting paid.

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Frequently Asked Questions

How much house can I afford on a $90,000 salary?As a general rule, buyers can afford a home priced at 3–4.5 times their annual gross income, depending on existing debts, down payment, and interest rate. On a $90,000 salary with a 10% down payment at 7% interest and minimal existing debts, a buyer could typically afford a home in the $280,000–$360,000 range. Use the calculator above for a precise figure based on your actual numbers.

What is a good debt-to-income ratio for a mortgage?Most conventional lenders prefer a total DTI of 36% or lower. FHA loans allow up to 43%, and some lenders will approve loans up to 50% DTI for highly qualified borrowers. A lower DTI not only improves approval odds but typically results in better interest rate offers.

How much down payment do I need to buy a house?Conventional loans typically require 3–20% down. Putting less than 20% down triggers PMI, which adds to your monthly cost. FHA loans require 3.5% down. VA and USDA loans offer 0% down payment options for qualifying buyers. A larger down payment reduces your loan amount, monthly payment, and total interest paid over the life of the loan.

Does the interest rate make a big difference in affordability?Yes — significantly. On a $400,000 loan over 30 years, the difference between a 5% and 7% interest rate is approximately $490 per month and over $176,000 in total interest paid. Even a half-point rate improvement meaningfully increases purchasing power.

What is PMI and when do I have to pay it?PMI, or Private Mortgage Insurance, is required on conventional loans when the down payment is less than 20% of the purchase price. It protects the lender — not the buyer — against default. PMI typically costs 0.5–1% of the loan amount per year and can be cancelled once the loan balance reaches 80% of the home's original value.