The three ways to get a home value estimate
You can find out what your home is worth by using an online estimate tool, hiring an appraiser, or asking a real estate agent to do a comparative market analysis. Each method costs different amounts and gives you different levels of detail. Online tools are free and instant but less precise. Appraisers charge $300 to $600 and give you a formal document. Real estate agents do the work for free but are selling you something.
The method you pick depends on why you need the number. If you are refinancing a mortgage, your lender will order an appraisal and you will not have a choice. If you are selling, a real estate agent's analysis is standard. If you just want to know for your own records or for property tax disputes, an online estimate is usually enough to start.
Key Takeaways
- Online home value tools like Zillow, Redfin, and Realtor.com give free estimates in minutes but can be off by 5 to 20 percent depending on how recent your home's data is.
- A professional appraiser charges $300 to $600 and produces a formal report that lenders and courts will accept, but takes one to two weeks.
- Real estate agents provide a comparative market analysis at no cost to you, though they earn money if you list with them.
- Your county assessor's value is public record and free to look up, but is set for tax purposes and often differs from market value.
- The most accurate estimate comes from combining multiple sources rather than relying on any single number.
Online home value estimators and how accurate they are
Free online tools pull data from public records, recent sales of similar homes, and property characteristics you enter yourself. The major ones are Zillow (which calls its estimate a "Zestimate"), Redfin, Realtor.com, and Trulia. You enter your address, confirm or correct details about your home, and get a number in seconds.
These estimates are usually within 5 to 20 percent of actual market value, but the margin depends on how much recent sales data exists in your area. In a neighborhood where homes sell frequently, the estimate is more reliable. In a rural area or a neighborhood with few recent sales, the estimate can be much further off. The tools also update slowly when you make improvements to your home, so if you recently renovated, the estimate will not reflect that work yet.
Use an online estimate as a starting point, not a final answer. If you see a big difference between two tools, that is a sign the estimate is uncertain. Write down the date you checked, because the number will change as new sales data comes in.
What a professional appraiser does and when you need one
An appraiser is a licensed professional who visits your home, measures it, photographs it, checks the condition of the roof and foundation, and compares it to recent sales of similar homes in your area. They produce a formal written report that includes all of this detail. Banks, courts, and government agencies accept an appraisal as proof of value.
You need an appraisal if you are refinancing a mortgage, because your lender will order one and you will pay for it (usually $300 to $600, sometimes more for unusual homes). You may also want one if you are disputing your property tax assessment, because the assessor's office will consider an independent appraisal. If you are selling your home, you do not need to order an appraisal yourself — the buyer's lender will order one as part of their mortgage process.
Finding an appraiser: ask your lender for a referral, or search your state's appraiser licensing board website. The board name varies by state but is usually something like "State Board of Appraisers." You can also ask a real estate agent for names. Appraisals take one to two weeks from the time you schedule them.
Real estate agent market analysis and what it includes
A real estate agent will prepare a comparative market analysis (CMA) at no cost to you. They pull recent sales of homes similar to yours — same neighborhood, similar size, similar condition — and show you what those homes sold for. They also show you homes currently listed and homes that did not sell. From this, they estimate what your home should sell for today.
The CMA is more detailed than an online estimate because an agent knows the neighborhood, has access to the local multiple listing service (MLS), and can explain why one comparable home sold for more or less than another. They might note that a home two blocks away sold for less because it has a smaller lot, or that another sold for more because it was recently updated.
The catch is that a real estate agent benefits if you list your home with them, so they have an incentive to estimate high. If you get a CMA from an agent, get one from a second agent too. If the two estimates are very different, ask each agent to explain their reasoning. A good agent will show you the comparable sales they used and walk you through their logic.
Your county assessor's value and why it is different from market value
Your county assessor sets a value on your home every year or every few years for property tax purposes. This value is public record and you can look it up free on your county assessor's website. Search by address or parcel number.
The assessor's value is almost always lower than what your home would sell for on the open market. Assessors use different methods than appraisers, and they are trying to estimate value for tax purposes, not sale price. In some states, the assessor's value is capped by law and does not rise as fast as the market does. In other states, assessors lag behind market changes by a year or more.
You can challenge your assessor's value if you think it is too high. The process varies by county but usually involves filing a form and sometimes attending a hearing. If you have a recent appraisal that shows your home is worth less than the assessed value, bring that to the hearing. Many counties have a deadline in spring for filing a challenge, so check your county assessor's website for dates.
How recent sales of similar homes affect your estimate
The most reliable estimates come from homes that sold recently in your neighborhood and are similar to yours in size, age, condition, and lot size. If a home three blocks away sold six months ago for $350,000 and it is nearly identical to yours, that is strong evidence of your home's value. If the most recent comparable sale is two years old, the estimate is less reliable because the market may have moved.
Real estate agents and appraisers both use comparable sales, but they may pick different homes as comparable. An agent might include a home from a nearby neighborhood if there are not enough sales in your exact neighborhood. An appraiser might exclude a home that sold in a short sale or foreclosure because those sales do not reflect normal market conditions. Ask whoever is giving you an estimate to show you which homes they used as comparables and why.
The number of comparable sales matters too. If your neighborhood has ten homes that sold in the last three months, an estimate based on those is more solid than an estimate based on two sales. In a slow market or a rural area, you may have to go back six months or a year to find enough comparables.
Combining multiple estimates to get a realistic range
Rather than picking one number as "the" value of your home, think of your home's value as a range. Get an online estimate, look up your assessor's value, and if you are serious about selling or refinancing, get either an appraisal or a real estate agent's CMA. Write down all three numbers and the date you got each one.
If all three are close together, you have a narrow range and can be confident in it. If they are spread out, that tells you the estimate is uncertain — usually because there is not much recent sales data in your area, or because your home is unusual in some way. In that case, an appraisal is worth the cost because it will give you a defensible number.
Remember that value changes over time. An estimate from six months ago is less useful now. If you are using the number for a major decision — refinancing, selling, or a tax dispute — get a fresh estimate within the last month.
Frequently Asked Questions
Can I use an online estimate to refinance my mortgage?
No. Your lender will order a professional appraisal and will not accept an online estimate. You will pay for the appraisal, usually $300 to $600. The appraisal is required before your lender will approve the refinance.
Why is my Zillow estimate so different from my real estate agent's estimate?
Zillow's estimate is based on public data and algorithm. An agent's estimate is based on recent comparable sales they know about and their knowledge of the neighborhood. Agents have access to the MLS, which Zillow does not. If the two are very different, ask the agent to show you the comparable sales they used.
How often should I check my home's value?
If you are not planning to sell or refinance, checking once a year is enough. If you are actively considering selling, check every month or two because the market can move. After you make a major improvement like a new roof or kitchen, wait three to six months before checking again, because online tools update slowly.
Is my county assessor's value the same as my home's market value?
No. The assessor's value is usually lower and is set for tax purposes. It does not reflect what your home would sell for. If you think the assessor's value is wrong, you can file a challenge with your county, usually in spring.
What if I think my home is worth more than the appraisal says?
If you ordered the appraisal yourself, you can ask the appraiser to reconsider if you have evidence they missed something — like a recent renovation or a comparable sale they did not know about. If your lender ordered the appraisal for a refinance, you have limited options. You can ask the lender to order a second appraisal, but you will pay for it.