Zillow is a residential real estate marketplace that operates as one of the largest property data repositories in the United States. Beyond its core listing platform, Zillow exposes housing data through multiple channels: free public research metrics, APIs for commercial use, and a historical transaction database. The company’s data offerings serve investors, researchers, appraisers, and analytics platforms looking for valuation estimates, market metrics, rental pricing, or transaction histories at scale.
What Zillow Sells
Zillow offers several distinct data products. The Zestimate is a machine learning based automated valuation model covering approximately 100 million U.S. homes. The Rent Zestimate is a rental price estimate covering around 125 million properties. These estimates are accessible through a licensed API for commercial users and through the public-facing website.
Zillow Research publishes free housing market reports and datasets available as CSV downloads and through APIs, including the Zillow Home Value Index (ZHVI), market heat index, rent forecasts, and transaction counts. ZTRAX is a transaction and assessment database with public records across 2,750+ counties available to academic, nonprofit, and government researchers. Additionally, Zillow offers Bridge Interactive, a data platform providing access to MLS listings, public records, and property/rental Zestimate data through approved partnerships and broker licensing.
Key Features
The Zestimate API retrieves property, rental, and foreclosure valuations for approximately 100 million U.S. properties. Access requires approval and is designed for commercial business use.
The Zillow Home Value Index measures typical home values across regions and housing types, including single-family homes, condos, and multi-bedroom categories. ZHVI data is available in smoothed and raw formats, updated monthly. Monthly data is released on the 16th of each month, with reporting lag of 18-23 days. The ZHVI now incorporates neural network technology to adjust more quickly to market trends and incorporate sales transactions, tax assessments, and property characteristics. The index covers approximately 95% of U.S. housing stock by market value.
Zillow Research metrics include the Market Heat Index, which measures the balance of supply and demand for single-family and condo homes using engagement and listing performance data. Zillow Observed Rent Forecast provides month-ahead, quarter-ahead, and year-ahead rent predictions. For-Sale Inventory tracks active listings by region. The Zillow Observed Rent Index measures actual rental prices across the country. Data is updated on the 16th of each month for most CSVs, with weekly cadence available for select metrics, typically updated on Tuesdays.
The Rent Zestimate tool is available free on the Zillow website and through Rental Manager. It estimates monthly rental prices based on property attributes, comparable rentals, market trends, and owner-provided home details. The tool displays a rent range alongside the point estimate to reflect data availability and market volatility. Coverage includes 114-125 million homes depending on data availability by county.
ZTRAX contains more than 400 million detailed public records across 2,750+ counties, spanning over 20 years of transaction data including deed transfers, mortgages, foreclosures, tax delinquencies, and auctions. It also includes property characteristics, geographic information, and tax assessments for approximately 150 million parcels across 3,100+ counties. ZTRAX is updated quarterly. Data quality and temporal coverage vary by county, with some counties digitized back to the 1990s while others extend only to the mid-2000s.
API access through Bridge Interactive requires appropriate terms of use compliance. Data cannot be stored locally; Bridge requires proper attribution links back to Zillow. API access is available via authentication token and returns data in JSON format.
Pricing and Tiers
When searching their website to write this article, we couldn’t find clearly published pricing for the Zestimate API or other commercial data APIs. Access requires request submission through their developer portal with company information and intended use case. Bridge Interactive, Zillow’s partner platform for data access, also operates on an approval basis and requires appropriate licensing or partnership agreements.
Zillow Research data and ZTRAX are publicly available at no charge. The Rent Zestimate tool is free for individual property owners. Zillow Rental Manager offers free listing, with optional premium listing upgrades at $39.99 per 90-day period.
Pros and Cons
Pros:
- Covers approximately 100 million properties for Zestimate valuations, with high coverage of U.S. housing stock
- Free public access to ZHVI, market metrics, and transaction histories
- Neural network-based Zestimate incorporates multiple data sources and updates responsively to market changes
- ZTRAX provides rare access to 20+ years of transaction and assessment records across thousands of counties
- Monthly update cadence for major indices with relatively low reporting lag
- Rent Zestimate available for 114-125 million properties
- Historical data extends back to 1997 for ZHVI and several decades for ZTRAX
Cons:
- Zestimate API requires approval and is available only for commercial use; no public API for individual developers
- ZTRAX temporal coverage is uneven by county, with some areas having limited historical data
- Rent Zestimate accuracy varies significantly by location and data availability
- Accuracy of estimates depends on completeness and recency of public records and listing data
- Terms of Use restrict data storage and require specific compliance conditions
- Bridge Interactive requires MLS membership, broker licensing, or approved partnership status
Alternatives
- Dwellsy IQ sells unit-level rental data sourced directly from property management software, covering single-family and multifamily residential and commercial properties. The data is normalized across markets and supports pricing engines, AVMs, underwriting, and portfolio monitoring. Audiences include tech platforms, investors, banks, AVM providers, and researchers.
- Redfin Data offers listing, sold, and rental data derived from MLS and public sources, with a focus on the for-sale market. The platform provides market metrics and comparable sales data via APIs and reporting tools. Redfin Data primarily serves real estate professionals, agents, and market analysts.
- Realtor.com Data provides listing data, market statistics, and property information sourced from the NAR MLS and public records. It offers APIs and downloadable datasets for professionals. The platform is designed for brokers, agents, and real estate analytics platforms.
- HouseCanary is an AVM and valuation platform offering property valuations, risk scores, and rental estimates via API. It serves appraisers, lenders, investors, and property analytics platforms with property-level insights and market data.
- ATTOM Data provides public records, transaction history, property attributes, and market analytics across the U.S. The platform serves investors, appraisers, and research institutions seeking deed records, foreclosure data, and comparative property information.
FAQ
What is the difference between Zestimate and ZHVI?
The Zestimate is an individual property valuation estimate calculated using a machine learning model applied to a single home. The Zillow Home Value Index is a market-level index showing the typical home value in a geographic region, calculated from a large set of Zestimates trimmed for outliers. ZHVI provides regional price trends, while Zestimate provides property-specific estimates.
Can I access Zillow data via API?
Zillow offers APIs for commercial use through its Zestimate API (covering property and rental valuations) and through Bridge Interactive (covering MLS listings, public records, and Zestimate data). Both require approval and agreement with terms of use. No free, unrestricted public API is available. ZTRAX public records and Research metrics can be downloaded without API access.
How current is Zillow’s data?
Zillow Research metrics are updated monthly, typically on the 16th of each month. ZHVI data has a reporting lag of 18-23 days. The Rent Zestimate is updated regularly but update timing is not publicly specified. ZTRAX is updated quarterly. Listing data and marketplace transactions reflect real-time activity.
How accurate is the Zestimate?
Zestimate accuracy varies by property, market, and data availability. Zillow publishes a Rent Zestimate accuracy table showing performance at national, state, county, and metro area levels. The company has improved the neural Zestimate model to react more quickly to market trends. Individual estimate accuracy depends on the completeness of available property attributes and comparable sales data in that market.
Does Zillow provide rental data?
Yes, Zillow provides rental data through the Rent Zestimate tool, which estimates monthly rental prices and is free for individual property owners. The Rent Zestimate covers 114-125 million properties and is based on property attributes, comparable rental listings, and market trends. Rent Zestimate data is also available through the Zestimate API for commercial users.
