The three ways to estimate your home's value
You can find out what your home is worth by using an online estimate tool, hiring a professional appraiser, or asking a real estate agent to do a comparative market analysis. Each method gives you a different kind of number—some are free and take minutes, others cost money but are more detailed. Which one you need depends on why you're asking: selling your home, refinancing a mortgage, or just understanding your finances all point to different answers.
None of these methods will tell you the exact price someone will pay. A home's actual value only becomes real when someone buys it. What these tools do is give you a reasonable range based on what similar homes sold for recently, what the property looks like, and what the market is doing right now.
Key Takeaways
- Online estimate tools like Zillow, Redfin, and your county assessor's website are free and instant, but less accurate than professional methods.
- A professional appraiser costs $300 to $500 and produces a formal report that lenders and courts will accept, but takes one to two weeks.
- A real estate agent's comparative market analysis is free if you're considering selling, and based on actual recent sales in your neighborhood.
- Your county assessor's office has a public record of your home's assessed value, which is usually lower than market value because it's used for property taxes.
- The same home can have different values depending on the method used and the date of the estimate, because home values change with the market.
Online estimate tools: fast and free, but rough
Websites like Zillow, Redfin, Realtor.com, and Trulia let you type in your address and get an estimate in seconds. These tools use public records—recent sales, property taxes, square footage, age of the home—and run them through an algorithm to guess what your home is worth. Zillow calls theirs a "Zestimate," Redfin calls theirs a "Redfin Estimate." They're all doing the same thing.
The speed and cost are the main advantages: you get a number immediately and pay nothing. The disadvantage is accuracy. These tools don't know the condition of your roof, whether your kitchen was renovated last year, or that your neighbor's identical house sold for $20,000 more because it has a better view. Zillow itself says its estimates are within 5 percent of actual sale price about half the time, and off by more than 20 percent about one in five times. The further you live from recent sales of similar homes, the less reliable the estimate becomes.
These tools are useful for a quick sense of direction—whether your home is worth $300,000 or $500,000—but not for making financial decisions. If you're thinking about refinancing or selling, move to a more precise method.
Your county assessor's public records: official but outdated
Every county assessor's office keeps a public record of every property's assessed value. You can find this by searching your county assessor's website (search "[your county] assessor") and typing in your address. The record will show the assessed value, the land value, the building value, when it was last assessed, and sometimes recent sales history.
This number is official and comes from a government source, but it's usually lower than what your home would actually sell for. Assessed value is calculated for property tax purposes, not market value. A home assessed at $250,000 might sell for $320,000. The assessment also updates on a schedule—some counties reassess every year, others every three to five years—so the number may be months or years old.
The assessor's record is most useful as a starting point and a check on other estimates. If three different methods all say your home is worth around $300,000, and the assessor says $250,000, you know the assessed value is lower but probably in the right ballpark.
Professional appraisals: the most detailed and formal
A professional appraiser is a licensed person who visits your home, measures it, photographs it, notes its condition, and writes a formal report on what it's worth. This report includes comparable sales, an explanation of the neighborhood, details about the building itself, and the appraiser's reasoning. Appraisals typically cost $300 to $500 and take one to two weeks to complete.
Appraisals are more accurate than online tools because the appraiser sees the actual property and can account for things algorithms can't—a new roof, a finished basement, deferred maintenance, or a view. Banks and mortgage lenders require appraisals before they lend money, and courts will accept an appraisal as evidence of value in disputes. If you're refinancing, your lender will order the appraisal and you'll pay for it as part of the closing costs.
The main drawback is time and cost. You have to schedule an appointment, wait for the appraiser to visit, and then wait for the report. If you just want a rough idea of your home's value, an appraisal is overkill. If you're making a financial decision—refinancing, selling, or settling an estate—it's worth the investment.
Real estate agent comparative market analysis: free if you're selling
If you're thinking about selling your home, a real estate agent will prepare a comparative market analysis (CMA) at no cost. This is a report showing what similar homes in your neighborhood sold for in the last three to six months, what homes are currently listed for, and what the agent thinks your home is worth based on that data.
A CMA is based on actual recent sales, not an algorithm, so it's usually more accurate than an online estimate. The agent has access to the Multiple Listing Service (MLS), which shows every home that sold in your area, the sale price, and details about each property. An agent can explain why one comparable home sold for more or less than another—maybe it had a garage, or it was on a corner lot, or it needed work.
The catch is that you have to be willing to talk to an agent, and the agent's interest is in listing your home for sale. If you're not ready to sell, asking for a CMA can feel like you're committing to something. Many agents will do one anyway because they hope you'll list with them later. If you're genuinely exploring whether to sell, a CMA from a local agent is one of the most useful estimates you can get.
Why the same home can have different values on different days
Home values change constantly because they're based on what people are willing to pay right now. If interest rates drop and more buyers enter the market, values go up. If a recession hits and buyers disappear, values go down. A home worth $350,000 in January might be worth $340,000 in June if the market has cooled.
This is why the date of an estimate matters. An appraisal from six months ago is less reliable than one from last week. Online estimates update regularly as new sales data comes in, but they're still snapshots of a moving target. If you're using a home value estimate to make a decision, check the date and understand that the number is only good for a few weeks or months.
The method also affects the number. The same home might have a Zillow estimate of $310,000, an assessor value of $280,000, and an appraisal of $325,000. These aren't contradictions—they're different ways of measuring value for different purposes. The appraisal is usually the most reliable for actual market value, but it's also the most expensive to get.
Which method to use for different situations
If you're curious about your home's value and have no immediate plans, start with a free online estimate and your county assessor's record. These take five minutes and cost nothing. If the two numbers are in the same ballpark, you have a rough sense of what your home is worth.
If you're refinancing a mortgage, your lender will order and pay for an appraisal. You don't have to choose—the lender does. You'll see the appraisal value when the lender sends you the appraisal report, usually a week or two before closing.
If you're thinking about selling, contact a local real estate agent and ask for a comparative market analysis. This is free and based on actual recent sales in your neighborhood. It's the most useful estimate for understanding what your home might sell for.
If you need a formal value for a legal reason—a divorce settlement, an estate, a property tax appeal—hire a professional appraiser. The cost is worth it because the report will be accepted in court or by a government agency.
Frequently Asked Questions
How often should I check what my home is worth?
If you're not planning to sell or refinance, checking once a year is enough. Home values don't change dramatically month to month for most properties. If you're actively considering selling or refinancing, get a fresh estimate within the last month, because that's when the market data is most current.
Is my county assessor's value the same as my home's market value?
No. Assessed value is usually lower because it's calculated for property tax purposes, not for what your home would sell for. Your home might be assessed at $250,000 but worth $320,000 on the open market. The assessor's value is a useful reference point but not the same as market value.
Can I use an online estimate if I'm refinancing?
No. Lenders require a professional appraisal before they will refinance a mortgage. An online estimate is not acceptable because it's not a formal document and doesn't carry legal weight. Your lender will order the appraisal and you'll pay for it as part of the refinancing costs.
What if different methods give me very different numbers?
Check the dates—older estimates are less reliable. Look at the method—an appraisal is usually more accurate than an online tool. If an appraisal and an online estimate differ by a lot, the appraisal is more trustworthy because it's based on an actual inspection of your home. If you're making a big financial decision, the appraisal is worth the cost.
Do I need to pay to find out what my home is worth?
No. Online estimates and county assessor records are free. You only pay if you want a professional appraisal or if a lender orders one as part of a mortgage transaction. For a quick estimate, free tools are enough. For a formal decision, a paid appraisal is more reliable.