How to use it
- 1Enter a domain such as
example.com, an IP address such as8.8.8.8or an AS number such asAS13335. A full web address works too – the tool picks out the domain. - 2Click Look up. The tool asks the registry in charge of that name or address directly, over RDAP where the registry supports it and over classic WHOIS where it doesn’t.
- 3For a domain, you see whether it’s registered, its registrar, when it was registered and when it expires, its name servers and its status codes explained in plain words. If no one holds the name, the tool tells you it’s available.
- 4Click “Show raw response” to see exactly what the registry sent, and copy it if you need it for a support ticket or an abuse report.
What WHOIS and RDAP tell you
Every domain ending has a registry that keeps the official list of names under it – Verisign for .com, CZ.NIC for .cz, DENIC for .de. You buy a domain through a registrar, which enters it in that list. A WHOIS lookup asks the registry what it has on file: the registrar, the dates the domain was registered and last changed, when it expires, the name servers that answer for it and its status codes.
IP addresses and AS numbers are handed out by five regional internet registries: ARIN (North America), RIPE NCC (Europe and the Middle East), APNIC (Asia-Pacific), LACNIC (Latin America) and AFRINIC (Africa). Their records show which organisation holds a block of addresses, the exact range, the country it’s registered in and the abuse contact for reporting spam or attacks from it.
WHOIS dates from the 1980s and returns plain text in a different format at every registry. RDAP, its successor, returns structured JSON over HTTPS, and since January 2025 it has been the official source for all generic domain endings such as .com and .org. This tool uses RDAP wherever a registry offers it and falls back to WHOIS for registries that don’t yet.
Why the owner’s name is usually hidden
Since the GDPR took effect in 2018, registrars and registries hide the personal data of domain holders – names, addresses, phone numbers and email addresses show as redacted or are left out. Many owners also use a privacy service that appears in place of their details. Company names are still published by some registries, and this tool shows the registrant’s organisation and country whenever the registry provides them.
To reach the owner of a domain, contact its registrar: most offer a contact form that forwards your message without revealing the owner’s address. To report spam, phishing or malware, write to the abuse contact shown in the results. For legal matters, registrars may disclose the holder’s details if you show a legitimate, documented interest.
Status codes and what happens when a domain expires
Status codes such as clientTransferProhibited come from EPP, the system registrars use to manage domains. Codes that start with client are set by the registrar and codes that start with server by the registry. The “prohibited” locks are normal – they stop anyone from moving or changing the domain without the owner’s approval. clientHold or serverHold, on the other hand, means the domain has been taken offline.
A domain doesn’t become free the moment it expires. For generic endings such as .com, the registrar usually keeps it for a grace period of up to 45 days in which the owner can still renew. Then comes a 30-day redemptionPeriod, when the owner can restore it for a fee, and finally five days of pendingDelete before anyone can register it again. Country-code registries set their own rules, so the timing for .de, .cz or .uk differs.
Questions and answers
How do I find out who owns a domain?
Look the domain up here. If the registry publishes the registrant’s organisation, you’ll see it along with the country. Most personal details are hidden for privacy, but the registrar is always listed – use its contact form to reach the owner, or the abuse contact to report misuse.
How can I check if a domain name is available?
Enter the name and click Look up. If the registry has no record of it, the tool says it’s available and you can register it through any registrar. A domain that has expired but is still in its grace, redemption or pending-delete period shows as registered until the registry releases it.
What happens when a domain expires?
The registrar may switch off its website and email or show a parking page, but the owner can still renew it for a while. For .com and other generic endings there is typically a grace period of up to 45 days, then a 30-day redemption period with a restore fee, then five days until deletion. After that the name is free for anyone to register.
What is the difference between WHOIS and RDAP?
Both return registration data. WHOIS is an old text protocol where every registry uses its own format, while RDAP returns standardised JSON over HTTPS, supports internationalised domain names and finds the right server automatically through IANA. RDAP has replaced WHOIS for generic domain endings, and many country-code registries support it too.
What does a WHOIS lookup of an IP address show?
It shows which regional registry manages the address, the network block it belongs to, the organisation it’s registered to, the country of registration and an abuse email for reporting attacks or spam. It doesn’t show where a device physically is – use the IP lookup tool for an approximate location.