Registration Data Access Protocol (RDAP)

The Registration Data Access Protocol (RDAP) was designed by the The weirds working group of the Internet Engineering Task Force as a successor to the ageing WHOIS protocol.

RDAP provides access to information about Internet resources: domain names, autonomous systems, and IP addresses.

RDAP provides: aims to support users and developers of RDAP clients by providing a single end point for RDAP queries. aggregates information about all known RDAP servers. RDAP clients can send RDAP queries to, which will then redirect requests to the appropriate RDAP service.

How To Use

Client Implementers

If you are developing an RDAP client, configure it to send HTTP requests to<type>/<object>, where <type> is the object type (one of domain, nameserver, ip, autnum etc) and <object> is the object identifier (eg,, 64496, etc).

If knows of an RDAP service which is authoritative for this resource, your client will receive a 301 redirect to the appropriate URI. If no resource is known, you will receive a 404 error.

The rdapper client uses by default, and can be used to verify the behaviour of the service.

Server Implementers

If you are implementing an RDAP service, you can redirect queries for unknown objects to, and we will dispatch the client to the appropriate authority (if we know it).

List of Known RDAP Services

Name Registries

Number Registries

Note that the responses returned by the above services may not conform to the current draft specifications for RDAP.

Submit Feedback

If you would like to submit feedback, or operate an RDAP service that you would like to be added to, please click here (apologies for the captcha, but I get a lot of spam).

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