What is WHOIS Lookup?
WHOIS is an internet protocol used to query databases that store the registered users and assignees of internet resources — including domain names, IP address blocks, and autonomous system numbers. When a domain is registered, the registrant's contact information, registration date, expiry date, and nameserver details are recorded in a WHOIS database maintained by ICANN-accredited registrars. Many registrants use WHOIS privacy protection to mask personal contact details, but registrar, nameserver, and date information remains publicly accessible. WHOIS lookups are used by security researchers, legal teams, and domain investors to investigate ownership and history.