The Registration Data Access Protocol (RDAP) is the successor to WHOIS. Like WHOIS, RDAP provides access to information about Internet resources (domain names, autonomous system numbers, and IP addresses). Unlike WHOIS, RDAP provides: aims to support users and developers of RDAP clients by providing a "bootstrap server", i.e. 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, ip, autnum, entity etc) and <object> is the object identifier (eg,, 64496, etc).

HTTP Status Codes

Note that these status codes only apply to the service itself, not the registry RDAP services themselves.


IANA has recently launched an RDAP service. Each TLD has its own RDAP record at{TLD} ( now redirects to this server). You can also get an RDAP search result listing all TLDs using

Additional Resources

Apart from the DNS, ASN and IP registries which are listed in the IANA registry, and IANA's own RDAP server, RDAP.ORG also provides an RDAP service for ICANN-accredited registrars. You can obtain RDAP records for ICANN-accredited registrars at{NNNN}-iana where {NNNN} is the numeric IANA ID. These records are synthesised from data published by IANA and ICANN.


These are the authoritative references for the RDAP protocol specifications:

Many RDAP servers have also implemented their own custom extensions, some of which may be found in the RDAP Extensions registry at IANA.

Privacy Considerations

If you use to perform RDAP queries, your queries will be logged, alongside your IP address. These logs are not disclosed to anyone and are deleted within a few days. will not set any cookies in your browser.


If you would like to submit feedback, please email

Supporting RDAP.ORG

If your organisation depends on, then please consider supporting it, since it's not free to operate and requires ongoing maintenance and management.

If you'd like to support this service, please email to discuss options.


You can review the code which uses on GitHub. is maintained by me, Gavin Brown. While I am currently an employee of ICANN, I run this service in my own time and at my own cost.