The Whois system has been replaced with RDAP.

It’s official.

Starting today, Whois is no longer the definitive source of domain name ownership data. It’s now the Registration Data Access Protocol (RDAP).

This won’t mean much to most internet users seeking information about domain name owners. RDAP has much of the same information that Whois does (and most ownership data is obscured by privacy services).

However, as DomainTools CEO Tim Chen explained on Domain Name Wire Podcast #517, many systems have been built to use Whois data. These systems might break when registrars and registries stop running Whois in parallel with RDAP.

Technically, registrars and registries can turn off Whois now. Chen believes many will continue to operate Whois for a while because of these dependencies.

RDAP can be accessed on ICANN’s website.

From a nomenclature standpoint, Domain Name Wire will likely continue to use the term Whois when referring to RDAP.