This WHOIS Lookup tool displays registration data for IPs, autonomous systems, or domains, including gTLDs, such as .COM, .EDU, etc., and country-code TLDs, such as .CA, .UK, etc.
The tool can lookup WHOIS database registration and ownership records for domains, IP addresses, or autonomous systems (AS). It can be also used to check if a particular domain name has been already registered or is available for registration.
This tool accepts an IPv4, IPv6, autonomous system number (ASN), domain name, host name (FQDN), URL, or email address as input. It will attempt to extract the actual domain name to query from the entered string. In some cases, specifically, for country-level domains with unknown or complex second-level domain structure, the input string may need to be adjusted (shortened) if lookup does not return the expected result.
The tools determines the right WHOIS server to query by using information either from the custom TLD & ccTLD server list or from the IANA Root Zone Database.
WHOIS is a widely used internet service that allows users to look up registration and ownership information of domains, autonomous systems, or IP addresses. This service is commonly used by network administrators, law enforcement, domain buyers, and researchers to gather details such as the registrar, the registration date, and contact information associated with the domain or allocation information for IP addresses and autonomous system numbers.
A typical WHOIS lookup can provide various types of data, including the domain owner's name (or organization), email address, phone number, registration and expiration dates, as well as details about the domain registrar and the nameservers being used. For IP addresses, WHOIS can reveal the organization to which the IP address is assigned and its location details. This information can help with troubleshooting network issues, investigating online abuse, and verifying the legitimacy of a website.
While WHOIS can provide valuable transparency, privacy concerns have arisen, particularly regarding the exposure of personal information. To address these concerns, domain privacy services (also known as WHOIS protection services) are often used to mask personal contact details in the public WHOIS records. Additionally, policies such as the GDPR in the EU have led to the redaction of personal data in WHOIS records to protect user privacy. Instead, the public may see only limited or proxy contact details, reducing the risk of misuse.
See Also
IANA - Root Zone Database
IANA - IPv4 Address Space Registry
IANA - Internet Protocol Version 6 Address Space
IANA - IPv6 Global Unicast Address Assignments
IANA - IANA IPv6 Special-Purpose Address Registry
RFC 1480 - The US Domain
TLD and ccTLD whois server list
Mozilla - The Public Suffix List