The Zestimate® is Zillow’s estimate of a home’s market value. It incorporates public records, MLS data and user-submitted home details into Zillow’s proprietary home valuation model. The Zestimate provides a transparent, free starting point to help homeowners, buyers and sellers better understand what a home may be worth and make informed decisions. It is not an appraisal and can’t be used in place of an appraisal.
You can view detailed accuracy statistics for on-market and off-market homes by region below.
Zillow publishes Zestimate home valuations for 110+ million homes across the country and uses state-of-the-art statistical and machine learning models that analyze hundreds of data points for each property.
To calculate a Zestimate, Zillow uses a neural network–based model that incorporates data from county and tax assessor records and direct feeds from multiple listing services (MLS). The Zestimate also incorporates:
In addition to a single Zestimate value, we provide an estimated sales range. The Zestimate reflects the model’s best estimate of a home’s market value, but actual sale prices can vary due to negotiation and changing market conditions. The estimated range captures this uncertainty and shows the span of prices the home could reasonably sell for given the information available at the time. The Zestimate represents the most likely outcome, while the range reflects how results may vary around that estimate.
The latest Zestimate model is built on an updated neural network–based architecture and incorporates expanded historical data to improve accuracy across both on-market and off-market homes. It better reflects recent sales activity, listing signals and changing market conditions, making the estimate more responsive to local trends and seasonality. These improvements have helped reduce overall error rates while maintaining fast processing and broad coverage.
The amount of data we have for your home and homes in your area directly affects the Zestimate's accuracy, including the amount of demand in your area for homes. If the data is incorrect or incomplete, update your home facts — this may affect your Zestimate.
To ensure the most accurate Zestimate, consider reporting any home updates to your local tax assessor. Unreported additions, updates and remodels aren't reflected in the Zestimate.
Check that your tax history and price history (the sale price and date you bought your home) are accurate on Zillow. If data is missing or incorrect, let us know.
Be aware that the model that creates the Zestimate factors in changing market trends, including seasonal fluctuations in demand. So in some cases that may be the reason for a change in your Zestimate.
When a home goes on the market, new data can be incorporated into the Zestimate model. For on-market homes, the Zestimate includes listing information such as the list price and recent market activity, which provide additional signals about the home’s likely sale price. This information is not available when a home is off-market, so the estimate may adjust once the listing goes live.
The Zestimate reflects comparable sales, listing details and current market conditions, and does not simply mirror the list price. In addition, properties that have been listed for an extended period may transition to off-market valuations if they have been listed longer than typical for that local market. In some cases, this may occur after a home has been listed for about a year or longer, depending on the market. This can result in a larger difference between the list price and the Zestimate.
Updates to your home facts are incorporated into the Zestimate. However, if the updates are not likely to affect the home’s value (for example, cosmetic updates), your Zestimate may not change. Zestimates for most homes update multiple times per week, although updates may occasionally be delayed due to system enhancements or model improvements.
The Zestimate uses complex, proprietary models that analyze millions of data points to estimate how changes to a home may affect its value. The algorithms determine the approximate added value that an additional bedroom, bathroom or renovations contributes, though the amount of the change depends on many factors, including local market trends, location and other home facts.
Keeping your home facts accurate and up to date helps ensure the Zestimate reflects the most current information available about your home.
Zillow has data on more than 125 million homes and publishes Zestimates for most of them. If your home does not have a Zestimate, it is typically because we do not yet have sufficient reliable data to generate an estimate that meets our accuracy standards. This can occur when information about the property is incomplete or inconsistent, when the model determines the estimate would be too uncertain, or in areas with limited recent sales activity.
For on-market homes, a Zestimate may also be hidden at the request of an owner or agent in accordance with certain MLS rules.
Zestimates are available only for residential properties. Large multi-family buildings, vacant land and commercial properties are not eligible.
Even if a Zestimate is not available, we may still display publicly available home details (such as bedroom and bathroom counts) and, depending on your location, tax-assessed or market-assessed values from the local taxing authority. These values are provided by government agencies and are not Zillow estimates.
No. The Zestimate is not an appraisal and can't be used in place of an appraisal. It is a computer-generated estimate of the value of a home today, given the available data.
We encourage buyers, sellers and homeowners to supplement the Zestimate with other research, such as visiting the home, getting a professional appraisal of the home, or requesting a comparative market analysis (CMA) from a real estate agent.
Zillow displays a Zestimate history chart that shows how our estimated market value for a home has changed over time. These historical Zestimates are calculated using the data available at each point in time. When sufficient data exists, you can view up to 10 years of history on a home’s detail page. The values shown are automated estimates designed to illustrate trends, not past appraisals.
We occasionally recalculate historical Zestimate values along with major data upgrades or improvements to the algorithm. These recalculations are based on a variety of considerations and, therefore, not every new algorithm release will get a corresponding update of historical values.
However, we never allow future information to influence a historical Zestimate (for example, a sale in 2019 could not influence a 2018 Zestimate). Historical Zestimates only use information known prior to the date of that Zestimate.
Yes — Zillow’s researchers and engineers continuously refine the Zestimate to improve accuracy. Since Zillow was founded in 2006, we have spent nearly 20 years developing and enhancing the model through multiple major updates and ongoing incremental improvements.
We refresh Zestimates for all homes multiple times per week. On rare occasions, updates may be delayed due to model enhancements or system improvements.
No. The Zestimate is intended to provide an estimate of the price that a home would fetch if sold for its full value, where the sale isn't for partial ownership of the property or between family members. Our extensive analysis of foreclosure resale transactions supports the conclusion that these sales are generally made at substantial discounts compared to non-foreclosure sales. For this reason, the Zestimate does not incorporate data about these sales.
The Zestimate is an automated valuation calculated by a software process. It's not possible to manually alter the Zestimate for a specific property.
We do not delete Zestimates. However, for some homes we may not have enough data to provide a home valuation that meets our standards for accuracy. In these instances, we do not publish the Zestimate until more data can be obtained
The Zestimate is designed to be a neutral estimate of a home’s fair market value, based on publicly available and user-submitted information. To ensure consistency and fairness, the model is applied uniformly across homes using standardized data such as bedroom and bathroom counts, square footage, lot size, tax assessments and prior sales.
Zestimates rely on much more than comparable sales in a given area. The home's physical attributes, historical information and on-market data all factor into the final calculation. The more we know about homes in an area (including your home), the better the Zestimate.
Our models can find neighborhoods similar to yours and use sales in those areas to extrapolate trends in your housing market. Our estimating method differs from that of a comparative market analysis completed by a real estate agent. We use data from a geographical area that is much larger than your neighborhood — up to the size of a county — to help calculate the Zestimate. Though there may not be any recent sales in your neighborhood, even a few sales in the area allow us to extrapolate trends in the local housing market.
The Zestimate is designed to provide an independent, data-driven estimate of a home’s market value based on available information and recent sales activity. It is intended to promote transparency and help consumers make informed decisions. The Zestimate reflects market conditions — it does not set or influence a home’s list price, and it should not be used to drive up the price of a home. The Zestimate is intended to track the market, not drive it.
No. The Zestimate is an automated valuation and not an appraisal. Most lending professionals and institutions will only use professional appraisals when making loan-related decisions.
If you see two Zestimates for the same property, please let us know through Zillow Customer Support. You may see more than one Zestimate for your address if you are a homeowner with multiple parcels of land. Zillow matches the parcels on record with the county. If you officially combine parcels, the county will send us updated information.
For nearly 20 years, the Zestimate has served as a widely used starting point for understanding home value. Millions of consumers visit Zillow each month, often forming their first impression of a home through its listing and Zestimate.
When combined with the expertise of real estate professionals, the Zestimate can help clients make more informed decisions. Agents can also help clients claim their home on Zillow, update home facts and reflect improvements made to the property. Accurate, up-to-date information ensures the Zestimate and listing provide the strongest and most transparent representation of the home.
