A Whois lookup is a query tool used to find detailed registration information about a domain name or an IP address. It provides data such as the domain's ownership, registration and expiration dates, contact details of the registrant, administrative and technical contacts, nameservers, and the registrar through which the domain was purchased
. The Whois database is maintained by domain registries and registrars under the oversight of ICANN (Internet Corporation for Assigned Names and Numbers). It acts like a public directory or address book that records who owns a domain and other relevant registration details. When a domain is registered, the owner must provide accurate contact information, which is then publicly accessible unless privacy protection services are used
. Whois lookups can be performed by entering a domain name or IP address into a Whois search tool available on various websites such as DomainTools, ICANN Lookup, GoDaddy, Namecheap, and others. These tools query the appropriate databases and return the most recent registration records within seconds
. Uses of Whois lookup include:
- Verifying domain ownership and registration status
- Contacting domain owners for business or legal reasons
- Investigating suspicious domains for cybersecurity purposes
- Troubleshooting network or DNS issues
- Researching domain registration trends and history
There are two main models of Whois data: thin Whois (basic info like registrar and registration dates) and thick Whois (more detailed info including contact details). Modern protocols like RDAP are also used to provide structured, secure access to registration data
. In summary, Whois lookup is an essential tool for accessing public domain registration data to identify domain owners, verify domain status, and support administrative, legal, and cybersecurity activities on the internet.
