Whois
Look up domain registration, IP allocation, or ASN ownership.
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What does Whois show?
Whois returns the public registration record for a domain name, IP address, or ASN. For domains this includes the registrar, registration and expiry dates, nameservers, and registrant contact details (often redacted for privacy). For IPs and ASNs it shows the network block owner and abuse contact.
Why are registrant details hidden or redacted?
Since 2018, GDPR and similar privacy regulations have required registrars to redact personal contact details from public Whois records. Most domains now show a privacy-protected contact or just the registrar's abuse address instead of the actual owner's name and email.
What is a domain registrar vs a registry?
The registry operates the TLD (e.g. Verisign runs .com). A registrar is an accredited company (like Namecheap, GoDaddy, or Cloudflare Registrar) through which you purchase domain names. The registry holds the authoritative database; registrars are the resellers.
What is the expiry date and why does it matter?
The expiry date is when the domain registration lapses if not renewed. An expired domain stops resolving — email bounces and the website goes offline — and the name may become available for anyone to register. Monitor expiry dates to avoid accidental lapses.
Can I look up an IP address or ASN with Whois?
Yes. Enter an IPv4 address (e.g. 8.8.8.8), IPv6, or an ASN (e.g. AS15169) to see the allocated block and its operator. This is useful for tracing the owner of a suspicious IP or verifying which ISP controls a network range.