What is the RESO Data Dictionary?
The RESO Data Dictionary is the real estate industry’s universal language for data. It allows a wide range of systems to talk to each other in a seamless manner.
The need for the Data Dictionary arose as the real estate industry evolved from printed MLS books to a digital experience. Thousands of REALTOR® associations and MLSs adopted unique technology systems to serve their local markets. These systems often couldn’t communicate with each other.
The Data Dictionary is the solution: a standard that ensures every system can speak the same language. It defines real estate data in consistent terms and structures. The Data Dictionary is a template for building systems that are flexible, scalable, and that will more easily integrate with other tools.
Visit the RESO Data Dictionary Wiki for the full list of data fields and options.
Benefits of the RESO Data Dictionary
Using the Data Dictionary creates concrete benefits for professionals and consumers:
- Simplified integrations: Standardized data moves between systems faster and allows tools to work together more accurately.
- Faster creation of new tools: Technology built on the standard brings new tools quickly to the market, saving time and money while creating more insightful data.
- The seal of approval: RESO certification provides a level of trust that data partners can rely upon.
- Promotion of leadership: The “RESO Certified” logo is a sign that an organization is leading the industry in moving standards forward.
- Collaboration with the industry’s best and brightest: Working with RESO’s 800+ member organizations provides significant benefits for industry newcomers and incumbents.
RESO Data Dictionary and Web API Technical Specifications and Testing Rules
These documents describe RESO’s specifications. Because MLSs certify Data Dictionary standards on the RESO Web API, both sets of specifications are important for technical developers to understand. By downloading these resources, you confirm that you agree to the RESO EULA.
Log in to RESO’s Confluence member hub to download the documents below. Contact email@example.com if you need login credentials.
- Data Dictionary 1.7 Specification
- Data Dictionary 1.7 Approved Spreadsheet
- Common Schema Reference Metadata (Web API Core 1.0.2+, DD 1.7)
- RCP – WEBAPI-031 Data Dictionary Representation in the Web API
- RESO Commander Testing Tool (on GitHub)
Does standardizing to the Data Dictionary take away flexibility for unique local factors?
While RESO’s Data Dictionary defines a standard for many kinds of data fields, it also allows for local markets to establish custom fields that reflect unique local situations. This can also be done in a standardized way which allows for flexibility while also ensuring interoperability between systems. The local real estate flavor can stay as unique as it always has.
New fields can also be added to the Data Dictionary to support industry needs. By joining RESO and collaborating with its workgroups, members can make suggestions for the expansion of standards. The Data Dictionary is continuously examined and expanded based on input from members across the industry. | VISIT THE DATA DICTIONARY WORKGROUP
Does the Data Dictionary support other languages?
While RESO’s Data Dictionary is in English at the data description level, it’s extensible to other languages. RESO has already explored multi-language display labels in Spanish and French Canadian for users of technology with Data Dictionary at its core. By using the Data Dictionary as the universal language for technology, and layering international and multi-language display labels on top, the local usage supports diverse customers while the interoperability remains.
RESO Data Dictionary Certification
RESO certifies MLSs, brokers, and technology partners on RESO’s Data Dictionary and Web API standards. In particular, MLSs owned and operated by REALTOR® associations are required by policy of the National Association of REALTORS® to be in compliance with RESO’s standards within 12 months of the standard being ratified by RESO. MLSs can show this compliance with a RESO certification.
Answers to Your Questions
Visit the RESO Certification Resources, or email firstname.lastname@example.org with questions.
Past RESO Data Dictionary Downloads, Certification Rules and Guides
RESO’s End User License Agreement (the “EULA”) is entered into by and between the Real Estate Standards Organization (“RESO”) and the person or entity (“End User”) that is downloading or otherwise obtaining the product associated with this EULA (“RESO Product”). By downloading past documents, you agree to the EULA. | VIEW ADDITIONAL DOWNLOADS
Data Dictionary Wiki Resources
The RESO Data Dictionary Wiki contains the resources, fields and lookups that guide the development of data systems.
RESO is grateful to the numerous industry experts who have helped craft the Data Dictionary. | ACKNOWLEDGEMENTS