The three ways to estimate your home's value
You can find out what your house 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 costs different amounts of money and gives you different levels of detail. Online tools are free but less precise. An appraiser costs $300 to $500 and produces a formal document. A real estate agent's analysis is usually free if you're thinking about selling.
The reason you need to know matters. If you're refinancing a mortgage, your lender will order an appraisal—you don't choose the method. If you're selling, a real estate agent's analysis tells you what buyers in your area are actually paying. If you're curious about your home's value for taxes or insurance, an online estimate is usually enough to start.
Key Takeaways
- Online home value tools like Zillow, Redfin, and Realtor.com are free and give you a ballpark figure in minutes, though they're based on public records and may be off by 5 to 20 percent.
- A professional appraiser produces a formal report that lenders accept, costs $300 to $500, and takes one to two weeks.
- A real estate agent's comparative market analysis is free, based on actual recent sales in your neighborhood, and is the most useful if you're planning to sell.
- Your home's assessed value for property taxes is usually lower than its market value and comes from your county assessor's office, not from what buyers would pay.
- The same house can have different values depending on who's measuring it and why—appraisers, agents, and online tools often disagree.
Using free online home value tools
Websites like Zillow, Redfin, Realtor.com, and Trulia let you enter your address and get an estimated value in seconds. These tools pull data from public records—your deed, tax assessments, recent sales of similar homes nearby—and run them through an algorithm. The estimate appears instantly and costs nothing.
The catch is accuracy. These estimates are often off by 5 to 20 percent, sometimes more. They work better in neighborhoods where homes sell frequently and are similar to each other. They work worse in areas where homes are unique, sales are rare, or recent renovations haven't been recorded yet. If your house is newly built, recently renovated, or very different from its neighbors, the online estimate may be significantly wrong.
Use an online tool as a starting point, not a final answer. Check the same address on two or three different sites—if they all say $350,000 to $380,000, you're probably in that range. If one says $300,000 and another says $420,000, the tool is uncertain and you need a more reliable method.
Hiring a professional appraiser
An appraiser is a licensed professional who inspects your home in person, measures it, photographs it, and compares it to recent sales of similar homes. They produce a formal appraisal report that lenders and courts accept as evidence of value. The cost is typically $300 to $500, and the process takes one to two weeks from the time you schedule the appointment.
You order an appraisal by calling appraisers in your area or asking your bank or mortgage lender for a referral. You pay upfront, and the appraiser schedules a time to visit. They'll spend 30 minutes to an hour inside and outside your home, taking photos and notes. They then spend several days writing the report, which you receive by mail or email.
An appraisal is necessary if you're refinancing a mortgage—your lender will order one and you'll pay for it as part of the refinance costs. If you're just curious about your home's value, an appraisal is more expensive than an online tool but more reliable. It's worth the cost if you need an official document or if your home is unusual enough that online estimates are unreliable.
Getting a real estate agent's market analysis
A real estate agent can provide a comparative market analysis (CMA), which is a report showing what similar homes in your neighborhood sold for recently. This is free if you contact an agent, because they're hoping you'll list your home with them. The analysis is based on actual sales, not algorithms, and it's usually more accurate than an online estimate for homes in active markets.
To get a CMA, contact two or three real estate agents in your area and ask them to prepare one. They'll visit your home, look at recent sales of comparable homes, and write a report showing the price range they think your home would sell for. This takes a few days. The report is theirs to give you, and you're under no obligation to list with them.
A CMA is the most useful estimate if you're planning to sell, because it's based on what actual buyers paid, not on an algorithm or a single appraiser's opinion. It also tells you what the local market is doing—whether homes are selling quickly or sitting on the market, whether prices are rising or falling. If you're not selling, a CMA is overkill; an online estimate or an appraisal serves the purpose better.
Understanding your home's assessed value for taxes
Your county assessor assigns your home an assessed value for property tax purposes. This is usually lower than what your home would sell for on the open market. The assessed value is public record and you can find it by searching your county assessor's website with your address.
Assessed value and market value are different things. A home might have a market value of $400,000 but an assessed value of $300,000. The assessor uses the assessed value to calculate your property tax bill. The assessed value is updated every few years, not every time the market moves. If you think your assessed value is too high, you can file a formal challenge with your county, but that's a separate process from finding out what your home is worth.
Don't confuse your assessed value with your home's actual value. They're calculated differently, updated on different schedules, and serve different purposes. Your assessed value is useful for understanding your property tax bill, but it's not what a buyer would pay.
Why different sources give different answers
You might get three different numbers depending on which method you use. An online tool might say $375,000. An appraiser might say $385,000. A real estate agent might say $360,000 to $395,000. This happens because each method looks at different data and makes different assumptions.
Online tools use algorithms trained on historical data. Appraisers use their judgment and experience. Real estate agents use recent sales in your specific neighborhood. All three are looking at real information, but they weight it differently. An appraiser might focus on the condition of your roof and foundation. An agent might focus on how quickly similar homes sold. An online tool might not know about a recent renovation.
If you're getting wildly different numbers, the most likely reason is that your home is unusual—it's much larger or smaller than neighbors, it's been heavily renovated, or it's in a neighborhood where sales are rare. In that case, an appraisal or an agent's analysis will be more reliable than an online tool.
When to use each method
| Reason you need the value | Best method | Cost | Timeline |
|---|---|---|---|
| Curious about home value | Online tool (Zillow, Redfin) | Free | Instant |
| Planning to sell | Real estate agent's CMA | Free | 3 to 5 days |
| Refinancing a mortgage | Professional appraisal (lender orders it) | $300–$500 | 1 to 2 weeks |
| Challenging property taxes | County assessor's records + appraisal | $300–$500 | 1 to 2 weeks |
| Estate or divorce settlement | Professional appraisal | $300–$500 | 1 to 2 weeks |
Frequently Asked Questions
How accurate are online home value estimates?
Online estimates are usually within 5 to 20 percent of actual value, but can be much further off for unique homes, newly built homes, or homes in neighborhoods with few recent sales. They're useful as a starting point but shouldn't be treated as a final answer. Check multiple sites to see if they agree.
Do I need an appraisal if I'm just curious about my home's value?
No. An online tool is free and gives you a ballpark figure. An appraisal costs $300 to $500 and is worth it only if you need an official document or if your home is unusual enough that online estimates are unreliable.
Can I use an online estimate to challenge my property taxes?
Most counties won't accept an online estimate as evidence. You'll need a professional appraisal or a real estate agent's analysis. Check your county assessor's website for the specific documents they require for a tax challenge.
What's the difference between an appraisal and a CMA?
An appraisal is a formal document from a licensed professional that lenders and courts accept. A CMA is an informal report from a real estate agent based on recent sales. Appraisals cost money; CMAs are free. CMAs are more useful if you're selling; appraisals are necessary for refinancing.
Should I get multiple appraisals to compare?
Usually not. One appraisal is enough for most purposes. If you're challenging a lender's appraisal or settling an estate, a second appraisal might be worth the cost, but for routine purposes, one is sufficient.