What is WHOIS data used for?

WHOIS is indispensable to the smooth operation of the DNS and is used for many legitimate purposes, including:

  • To determine whether or not a given domain is available.
  • To contact network administrators for resolution of technical matters related to networks associated with a domain name (e.g., DNS or routing matter, origin and path analysis of DoS and other network-based attacks).
  • To diagnose registration difficulties. WHOIS queries provide information that is often useful in resolving a registration ownership issue, such as the creation and expiration dates and the identity of the registrar.
  • To contact web administrators for resolution of technical matters associated with a domain name.
  • To obtain the real world identity, business location and contact information of an online merchant or business, or generally, any organization that has an online presence.
  • To associate a company, organization, or individual with a domain name, and to identify the party that is operating a web or other publicly accessible service using a domain name, for commercial or other purposes.
  • To contact a domain name registrant for the purpose of discussing and negotiating a secondary market transaction related to a registered domain name.
  • To notify a domain name registrant of the registrant's obligation to maintain accurate registration information.
  • To contact a domain name registrant on matters related to the protection and enforcement of intellectual property rights.
  • To establish or look into an identity in cyberspace, and as part of an incident response following an Internet or computer attack. (Security professionals and law enforcement agents use WHOIS to identify points of contact for a domain name.)
  • To gather investigative leads (i.e., to identify parties from whom additional information might be obtained). Law enforcement agents use WHOIS to find email addresses and attempt to identify the location of an alleged perpetrator of a crime involving fraud.
  • To investigate spam, law enforcement agents look to the WHOIS database to collect information on the website advertised in the spam.