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Registry Operators

Registry operators are the organizations that maintain the master database of all domain names registered under a particular generic top-level domain (gTLD).

Registration Data Access Protocol (RDAP) FAQs

What is RDAP?

RDAP is a protocol that delivers registration WHOIS-like data, but in istandardized data access and query response formats. Additional benefits of RDAP include support for internationalization, secure access to data, and the ability to find authoritative servers.

RDAP functions are fundamentally different from WHOIS. A WHOIS query is limited to the specific database queried, be it a registry operator or registrar's registration data database. By contrast, RDAP also has a functionality known as "bootstrap" that enables a query to go beyond a specific registry operator or registrar to enable a search of all registration data available in the RDAP service. Instead of returning a result such as "not available," a query will route to the authoritative server to return the relevant data. This is different from the current WHOIS protocol, where the information is not linked across contracted party systems. This enables broader searches while at the same time minimizing the amount of data that is routinely transferred from one entity to another.

Why is RDAP now a requirement for ICANN contracted parties?

Deficiencies with the WHOIS system, such as lack of support for internationalization, secure access to data, differentiated access, standardized query, response, and error responses, have been recognized for over a decade. ICANN's Security and Stability Advisory Committee advised in 2011 that the ICANN community evaluate and adopt a replacement protocol. SAC 051: SSAC Report on Domain Name Whois Terminology and Structure [PDF, 243 KB].

Will RDAP replace web-based and port 43 WHOIS?

All gTLD registries and registrars are required to provide RDAP services using the gTLD RDAP Profile, but as of 28 January 2025 they are no longer required to provide WHOIS services or web-based WHOIS services (except for .com, .name, and .post).

Will RDAP implementation require registry operators or registrars to make any changes to existing registration data?

RDAP implementation will not require changes to the data that is already stored and accessed via WHOIS; it is simply a new way of accessing that registration data.

The registration data is the same, but the structure of the response is different. Having said that, an RDAP client is likely to format the response in a way that is user-friendly and perhaps similar to the WHOIS format, at least at the onset of RDAP deployment.

How can a third party access registration data using RDAP?

RDAP is a protocol, not a website an entity can visit to access registration data. RDAP is used using a command line utility, lookup software, or third-party website. ICANN has set up the RDAP Web Client which third parties are free to use. More information regarding RDAP clients can be found here.

Are gTLD registries or registrars required to implement RDAP?

Yes all, gTLD registries and registrars were required to implement an RDAP service by 26 August 2019. If you are a gTLD registry or registrar, you may want to review our resources for RDAP Implementers.

How do I update the RDAP Base URL or Sponsored domain for my registrar?

Both the RDAP Base URL and sponsored domain for a registrar may be updated through the Naming Service Portal (NSp). More information on NSp may be found here.

For further information, contact Global Support.