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.

Additional Resources

Apart from the DNS, ASN and IP registries which are listed in the IANA registry, RDAP.ORG also provides the following unofficial RDAP server endpoints:


These are the authoritative references for the RDAP protocol specifications:

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.

Submit Feedback

If you would like to submit feedback please click here.


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.

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.