Home Buying Affordability Calculator

Affordability Calculator

Use Zillow’s affordability calculator to estimate a comfortable mortgage amount based on your current budget. Enter details about your income, down payment and monthly debts to determine how much to spend on a house.

AFFORDABILITY CALCULATOR TO BUY A HOME

Factors that impact affordability

When it comes to calculating affordability, your income, debts and down payment are primary factors. How much house you can afford is also dependent on the interest rate you get, because a lower interest rate could significantly lower your monthly mortgage payment. While your personal savings goals or spending habits can impact your affordability, gettingpre-qualified for a home loan can help you determine a sensible housing budget.

How to calculate affordability

Zillow’s affordability calculator allows you to customize your payment details, while also providing helpful suggestions in each field to get you started. You can calculate affordability based on your annual income, monthly debts and down payment, or based on your estimated monthly payments and down payment amount.

Our calculator also includes advanced filters to help you get a more accurate estimate of your house affordability, including specific amounts of property taxes, homeowner’s insurance and HOA dues (if applicable). Learn more about the line items in our calculator to determine your ideal housing budget.

Annual income

This is the total amount of money earned for the year before taxes and other deductions. You can usually find the amount on your W2 form. If you have a co-borrower who will contribute to the mortgage, combine the total of both incomes to get your annual income.

Total monthly debts

These are recurring monthly expenses like car payments, minimum credit card payments or student loans. You can adjust this amount in our affordability calculator as needed. For example, if you have a $250 monthly car payment and $50 minimum credit card payment, your monthly debt would be $300.

Down payment

The amount of money you spend upfront to purchase a home. Most home loans require a down payment of at least 3%. A 20% down payment is ideal to lower your monthly payment, avoid private mortgage insurance and increase your affordability. For a $250,000 home, a down payment of 3% is $7,500 and a down payment of 20% is $50,000.

Debt-to-income ratio (DTI)

The total of your monthly debt payments divided by your gross monthly income, which is shown as a percentage. Your DTI is one way lenders measure your ability to manage monthly payments and repay the money you plan to borrow. Our affordability calculator will suggest a DTI of 36% by default. You can get an estimate of your debt-to-income ratio using our DTI Calculator.

Interest rate

The amount that a lender charges a borrower for taking out a loan. Typically, the interest rate is expressed as an annual percentage of the loan balance. The borrower makes payments (with interest) to the lender over a set period of time until the loan is paid in full. Our affordability calculator uses the current national average mortgage rate. Your interest rate will vary based on factors like credit score and down payment. Calculate your mortgage interest rate.

Loan term

The length by which you agree to pay back the home loan. The most common term for a mortgage is 30 years, or 360 months, but different terms are available depending on the type of home loan that works best for your situation. You can edit your loan term (in months) in the affordability calculator’s advanced options.

Property tax

When owning a home, you pay annual property taxes based on the assessed value of the property or purchase price of the home, which can affect your affordability. The tax rate you pay can vary by state, county and municipality. Our calculator assumes a property tax rate by default, but you can edit this amount in the calculator’s advanced options. To obtain a more accurate total payment amount, get pre-qualified by a lender.