How Accurate Are Online Home Value Estimates? How to Find What Your Triangle Home Is Worth

Caul Group Residential, brokered by eXp Realty

Online home value estimates are a good starting point, and they are most accurate for homes that are listed for sale. For homes that are not on the market, Zillow says its median error is 7.20% and Redfin says 7.52%, so the best way to learn what your Triangle home is worth is a comparative market analysis from a local agent who knows your street and has seen your home.

Below we explain how these estimates work, what the sites themselves say about accuracy, and the steps that give you a value you can plan around. If you want a number for your own home, you can request a free home value report at any time.

How online home value estimates work

Sites like Zillow and Redfin use an automated valuation model, or AVM. The Consumer Financial Protection Bureau describes an AVM as "a computer-generated value that uses mathematical models" to compare a home's details, like bedrooms, bathrooms and square feet, with recent sales and other market information (CFPB).

Zillow says the Zestimate uses public records, MLS data and details owners submit, and that its model looks at home features, listing data, tax assessments, prior sales and market trends (Zillow). Redfin says its estimate uses "more than 500 data points about the market, the neighborhood, and the home itself" (Redfin).

Both companies say their estimates are not appraisals. Each one is a computer's best guess based on the data it has.

How accurate are they? What the sites publish

Both companies post their own accuracy numbers. These are the figures on their pages when we checked them on October 28, 2026:

• Zestimate: Zillow says "the nationwide median error rate for the Zestimate is 1.77% for homes that are on the market and 7.20% for off-market homes." In plain terms, half of estimates land within that range of the final sale price, and half are further off (Zillow).
• Redfin Estimate: Redfin says it has "a current median error rate of just 1.91% for homes that are for sale, and 7.52% for off market homes," meaning the estimate is within that range of the sale price half the time (Redfin).

A median error means half of homes come in closer than that number and half come in further away. Your home could be one of the close ones or one of the far ones, and the estimate alone cannot tell you which.

Why estimates vary more for some homes

Both sites say their estimates are more accurate for homes that are for sale, since a listing adds up-to-date details like the list price and recent market activity. Zillow also says accuracy "can also vary by location and property, as it depends on the depth and quality of available data."

Here is where an automated estimate has the hardest time:

• Your home is not listed. The model has no list price or other listing details to work with.
• Updates the records do not show. Zillow notes that "unreported additions, updates and remodels aren't reflected in the Zestimate." A new kitchen, finished basement or added bath may not count.
• Unique homes. Custom builds, homes on acreage and homes with few similar sales nearby can give the model less to compare.
• Condition. A computer cannot walk through your home, so it cannot see wear, quality of finishes or a fresh roof.
• Wrong facts. If the square footage, bedroom count or lot size on file is wrong, the estimate starts from the wrong place.

Zillow also says its model can use sales from an area much larger than your neighborhood, up to the size of a county, and that its method "differs from that of a comparative market analysis completed by a real estate agent" (Zillow).

Online estimate vs. tax value vs. CMA vs. appraisal

You may see four different numbers for the same home. Each one has a different job.

• Online estimate (AVM): a free, instant computer estimate. Good for tracking trends.
• County tax value: in Wake County, your assessed value "reflects the market value as of the most recent countywide revaluation, which was effective Jan. 1, 2024." The next revaluation will reflect market value as of January 1, 2027 (Wake County). It does not change with today's market until then.
• Comparative market analysis (CMA): North Carolina law defines a CMA as an estimate prepared by a licensed real estate broker of a home's probable selling price, with details on its condition, market, neighborhood and comparable homes. The same law says it "does not include an automated valuation model" (G.S. 93A-82).
• Appraisal: the CFPB calls an appraisal "a written document that shows an opinion of how much a property is worth" and "an independent assessment of the value of the property" (CFPB). When you buy or refinance, your lender may need a new appraisal.

A CMA is not an appraisal. When a North Carolina broker charges a fee for one, state law requires a written statement saying so (G.S. 93A-83).

Want to see what nearby homes actually sold for? Our guide on how to look up a home sale price in Wake County walks you through the county's free records.

What a local comparative market analysis adds

A CMA starts with the same kind of sales data an online model uses. The difference is the person reading it. A local agent can:

• Pick the sales that truly match your home, on your street or in your neighborhood, and set aside the ones that do not.
• Walk through your home and account for updates, condition, layout and lot.
• Look at homes that are for sale and under contract right now, not just past sales.
• Explain how your home compares, so you can choose a price and a plan with confidence.

How to find what your Triangle home is worth

• Check a few online estimates. Look at the range, not one number.
• Fix your home facts. Make sure square footage, beds, baths and updates are right on the sites and in the county records.
• Look up recent nearby sales. Use the county's records, as shown in our Wake County sale price guide.
• Get a free local CMA. Request a free home value report from our team, or call (919) 263-7653.
• Know when you need an appraisal. If the value is for a loan, ask your lender. Zillow notes that most lenders will only use professional appraisals for loan decisions (Zillow).

Thinking about selling?

A good price starts with a good number. Request your free home value report or call us at (919) 263-7653. To learn how the selling process works, visit our Sell My Home page.

Frequently asked questions

How accurate is a Zestimate?

Zillow says the nationwide median error rate for the Zestimate is 1.77% for homes that are on the market and 7.20% for off-market homes (as posted on its Zestimate page on October 28, 2026). That means half of estimates fall within that range of the final sale price and half fall further away.

How accurate is the Redfin Estimate?

Redfin says its estimate has a current median error rate of 1.91% for homes that are for sale and 7.52% for off-market homes (as posted on its Redfin Estimate page on October 28, 2026).

Which home value estimate is the most accurate?

No single online estimate is right for every home. Each site publishes its own error rates, and all of them are more accurate for homes that are listed for sale. For an off-market home, a comparative market analysis from a local agent who has seen the home gives you a value based on the closest matching sales.

Is a Zestimate the same as an appraisal?

No. Zillow says the Zestimate is not an appraisal and can't be used in place of one. An appraisal is a written opinion of value from a licensed appraiser, and your lender may need one when you buy or refinance.

Why is my tax value different from my home's market value?

In Wake County, assessed values reflect market value as of the last countywide revaluation, effective January 1, 2024. Market changes since then do not change your tax value until the next revaluation, which will reflect values as of January 1, 2027.

What is a comparative market analysis?

A comparative market analysis, or CMA, is an estimate from a licensed real estate broker of a home's probable selling price, based on its condition, market, neighborhood and comparable homes. North Carolina law says a CMA does not include an automated valuation model, and it is not an appraisal.

Sources checked October 28, 2026: Zillow, What is a Zestimate?; Redfin, About the Redfin Estimate; CFPB, different valuations; CFPB, appraisals; N.C.G.S. 93A-82; N.C.G.S. 93A-83; Wake County Revaluation FAQ. Online estimate figures change over time; check each source for the latest numbers.