Data Coverage and Zestimate® Accuracy

The home data we have compiled to generate a Zestimate home valuation varies by location. Some counties provide all the data we could hope for, but others are lacking such key things as the number of bedrooms and bathrooms, or, in some cases, the square footage of the home. The more data we have, the more accurate the Zestimate. And, we've made it easier for our users to help us improve accuracy by incorporating edited home facts into our Zestimate calculations. In some areas, we might not be able to produce a Zestimate at all, but we do have some basic information on the homes. The tables below show you where we have Zestimates and other home information.

To measure the accuracy of the Zestimates, we've gone back in time and compared the historic Zestimates with the actual transaction prices of homes that sold. The tables below also provide various measures of that accuracy.

What's a Zestimate?

A Zestimate home valuation is Zillow's estimated market value. It is not an appraisal. Use it as a starting point to determine a home's value. Learn more.

  • North Carolina Counties

North Carolina

County Zestimate Accuracy % Homes on Zillow % Homes With Zestimates Within 5% of Sale price Within 10% of Sale Price Within 20% of Sale Price Median Error
Alamance 99% 99% 25% 45% 65% 11.9%
Anson 99% 0% -- -- -- --
Brunswick 99% 0% -- -- -- --
Buncombe 99% 99% 27% 47% 71% 10.6%
Burke 99% 82% 13% 25% 47% 21.8%
Cabarrus 99% 99% 39% 60% 79% 7.4%
Caldwell 99% 85% 26% 45% 70% 11.5%
Catawba 99% 99% 20% 39% 64% 13.7%
Chatham 99% 0% -- -- -- --
Cleveland 62% 0% -- -- -- --
Craven 99% 0% -- -- -- --
Cumberland 99% 99% 45% 70% 88% 6%
Currituck 97% 0% -- -- -- --
Davidson 99% 96% 26% 42% 71% 11.7%
Davie 99% 0% -- -- -- --
Durham 99% 99% 35% 55% 74% 8.4%
Edgecombe 99% 0% -- -- -- --
Forsyth 99% 99% 36% 58% 78% 7.7%
Franklin 99% 99% 27% 45% 68% 11.1%
Gaston 99% 99% 31% 53% 75% 9%
Guilford 99% 99% 36% 60% 78% 7.7%
Harnett 99% 61% 25% 45% 67% 11.4%
Haywood 99% 99% 14% 24% 44% 23.4%
Henderson 99% 0% -- -- -- --
Iredell 99% 99% 26% 47% 68% 11.1%
Jackson 99% 0% -- -- -- --
Johnston 99% 71% 46% 69% 90% 5.8%
Lincoln 93% 93% 22% 47% 70% 10.7%
Macon 99% 0% -- -- -- --
Mecklenburg 99% 99% 40% 64% 82% 6.7%
Moore 99% 61% 28% 47% 74% 10.7%
Nash 68% 68% 34% 54% 81% 9%
New Hanover 99% 99% 33% 57% 78% 7.9%
Onslow 99% 99% 53% 76% 89% 4.5%
Orange 99% 0% -- -- -- --
Pitt 99% 99% 40% 65% 81% 6.7%
Randolph 99% 99% 20% 39% 66% 13%
Robeson 73% 0% -- -- -- --
Rockingham 99% 0% -- -- -- --
Rowan 66% 66% 27% 48% 74% 10.3%
Stanly 99% 0% -- -- -- --
Stokes 60% 0% -- -- -- --
Surry 25% 0% -- -- -- --
Union 99% 99% 38% 61% 79% 7.3%
Wake 99% 99% 48% 74% 90% 5.2%
Wayne 49% 0% -- -- -- --
Yadkin 99% 0% -- -- -- --

Last updated: January 3, 2008
Note: Zestimate accuracy is computed by comparing the final sale price to the Zestimate on or before the sale date. The data herein is computed for the three-month period ending Sept. 30, 2007.

Click here to download an Excel spreadsheet of this data.

Definitions

Zestimate Accuracy/Star Rating:
This rating is tied to the Median Error in an area.
The ratings are as follows:
  • Four Stars = Best Zestimate
  • Three Stars = Good Zestimate
  • Two Stars = Fair Zestimate
  • One Star = Tax assessor's value, or unable to compute Zestimate accuracy
  • 0 stars = No valuation
Close
Tax Assessor's Value

Depending on the jurisdiction where you live, this value could be the tax assessed, tax appraised, or market assessed value. This value comes from the taxing authority of the city, county or state where you live; this is not Zillow's value.

Note: Tax assessor's values differ from Zillow's Zestimate, which is computed by entering numerous data points into a proprietary formula, often resulting in a more accurate value estimate.

Homes on Zillow:
This indicates the percentage of homes for which we have data (e.g., number of bedrooms or bathrooms) in a particular locale. These are the homes you can find via maps or search on Zillow.com.
Homes With Zestimates:
We can only calculate Zestimates for homes where we have certain data, including transactions. This column indicates the percentage of homes in an area with Zestimates.
Within 5% of Sale Price:
This is the percentage of transactions in a location for which the Zestimate was within 5% of the transaction price. For example, in the Portland area, 40% of the time the Zestimate was within 5% of the selling price.
Within 10% of Sale Price:
This is the percentage of transactions in a location for which the Zestimate was within 10% of the transaction price.
Within 20% of Sale Price:
This is the percentage of transactions in a location for which the Zestimate was within 20% of the transaction price.
Median Error:
Half of the Zestimates in an area were closer than the error percentage and half were farther off. For example, in Seattle, Zestimates for half of the homes are within 6.6% of the selling price, and half are off by more than 6.6%.
pageName