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WHOIS Lookup

Look up the WHOIS registration data for any public domain, registrar, dates and nameservers.

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Frequently asked questions

What data does this tool send to your servers?
Only the domain name you enter is sent to our server to perform the WHOIS query. We do not record your IP address alongside your queries or retain any personally identifying information about you. The raw WHOIS response is returned to your browser and not stored on our infrastructure beyond the 10-minute response cache.
What is the WHOIS protocol and how does it work technically?
WHOIS is a simple TCP-based query/response protocol defined in RFC 3912. A client opens a TCP connection to port 43 on the WHOIS server, sends a plain-text domain name followed by a carriage return and line feed, and receives the registration data as a plain-text response. There is no authentication, encryption, or standardised response format — each registry formats its output differently, which is why parsing WHOIS is notoriously difficult.
Why is the registrant's contact information redacted?
Since GDPR came into effect in 2018, most registrars hide personal contact details (name, address, phone, email) from public WHOIS responses for registrations by natural persons in covered jurisdictions. Similar privacy regulations have been adopted elsewhere. Registrar information, registration dates, expiry dates, and nameservers remain public. If you have a legitimate legal need for redacted contact data, the registrar's RDAP service or a formal request process may provide a path to access it.
Are all TLDs supported?
Most global gTLDs (.com, .net, .org, .info, .biz) and the majority of country-code TLDs that publish a WHOIS server via IANA are supported. A handful of ccTLDs — notably .au (Australia) — use proprietary or RDAP-only registries not covered by the traditional WHOIS protocol and may return no data. New gTLDs introduced through ICANN's expansion program are generally supported.
Are there rate limits on WHOIS lookups?
Yes, on two levels. Our service applies per-IP rate limits to keep the tool free and available. Additionally, most registries impose their own rate limits on WHOIS queries and may temporarily block IPs that query too frequently — we cache results for 10 minutes partly to stay within those limits. For bulk lookups (checking hundreds of domains), use a dedicated registrar API or a commercial WHOIS service.
How does this compare to running 'whois' in a terminal?
The command-line 'whois' tool queries the same underlying servers and produces the same raw output, making the results functionally equivalent. This web tool additionally parses the key fields into a structured summary, making it easier to spot registration dates and nameservers at a glance without reading through the raw text. The terminal command can also be scripted for bulk queries, which this tool is not designed for.
What does 'clientTransferProhibited' mean in the domain status?
This status, set by the registrar, prevents the domain from being transferred to a different registrar without explicit action by the current registrar. It is a security measure against unauthorised transfers, sometimes called domain hijacking, and is considered best practice for active domains. 'serverTransferProhibited' is the same lock set by the registry rather than the registrar. Most legitimately registered domains will show one or both of these statuses.
Does this tool log WHOIS queries for analytics or advertising?
No. Domain names you look up are used only to fetch and return the WHOIS data to you. We do not build lookup histories, share domain query data with third parties, or associate lookups with user profiles. Anonymous aggregate statistics (total query volume) may be used for capacity planning.
What is the difference between WHOIS and RDAP?
RDAP (Registration Data Access Protocol, defined in RFC 7480) is the modern successor to WHOIS. It returns structured JSON instead of unformatted plain text, supports authentication for accessing redacted data, and provides consistent field names across registries. ICANN mandated RDAP support for all gTLD registries in 2019. Some TLDs are now transitioning away from WHOIS entirely. This tool currently uses the legacy WHOIS protocol for broad compatibility.
A domain shows as available in registrar searches but resolves in DNS — is that possible?
Yes. A domain can have DNS records (like a parking page) while its WHOIS registration has lapsed if the registrar or registry is operating a DNS hold or redemption grace period. Alternatively, the domain may be in a drop-catching queue. Always confirm availability through the registrar's own real-time availability check before assuming WHOIS availability data is definitive, since caching and redemption periods can cause discrepancies.

About WHOIS Lookup

WHOIS is the long-standing public directory that records who registered a domain name, which registrar manages it, when it was first created, when it is set to expire, and which nameservers are authoritative for it. The protocol dates back to 1982 and is defined by a series of RFCs that have evolved over decades. Each top-level domain (TLD) has one or more authoritative WHOIS servers, maintained either by the registry itself (like Verisign for .com) or the national registry for country-code TLDs. The data is publicly accessible because domain registration has historically been treated as a public record to facilitate abuse reporting, intellectual property protection, and network operations.

Domain investors and brand protection teams use WHOIS to track expiration dates and identify when valuable names are becoming available. Abuse and security teams look up registration dates and registrar details when investigating phishing campaigns or spam sources — a domain registered yesterday with a privacy proxy is a common red flag. Legal professionals use it to establish ownership evidence in trademark disputes. Network engineers consult it to find the right abuse contact when a domain is sending attack traffic. Everyday users can use it to check whether a domain they want to buy is taken, or to find out when a competitor's domain is due to renew.

This tool queries the authoritative WHOIS server for the TLD you enter and returns both a parsed summary of the key fields and the complete raw WHOIS response. We identify the correct WHOIS server from the IANA list rather than relying on a single aggregator, which means results are as fresh and accurate as the registry allows. Lookups are cached for 10 minutes server-side to reduce load on registry servers and comply with their rate-limiting policies. No personal data about the person performing the lookup is stored or logged.

When reading a WHOIS result, focus on the Registrar, Creation Date, Registry Expiry Date, and Name Servers fields for the most operationally useful information. If contact details appear as 'Redacted for Privacy' or point to a proxy service, that is normal since GDPR and similar regulations have led most registrars to hide personal contact information for registrations in covered jurisdictions. The Registrar IANA ID is a reliable numeric identifier you can use to look up the registrar's abuse contact directly on the IANA website if you need to report abuse. A domain in 'clientTransferProhibited' and 'serverTransferProhibited' status is locked against transfer, which is the normal secure state for an active domain.

The 40-Year-Old Directory That Still Runs the Internet

WHOIS is one of the oldest surviving internet protocols, first described by Elizabeth Feinler and her team at the Stanford Research Institute Network Information Center (SRI-NIC) in RFC 812 in 1982. The original purpose was simple: provide a way to look up the humans responsible for network resources, since the early ARPANET was a small community where accountability was informal but important. The protocol was intentionally minimal — plain text over TCP — because the machines of the era had very limited resources and complexity was a liability.

As the commercial internet grew through the 1990s, WHOIS became a point of significant controversy. The requirement to publish registrant contact details created a directory that spammers, stalkers, and data brokers could mine at scale. ICANN repeatedly discussed privacy reforms but was slow to act, leading to a patchwork of 'privacy proxy' services offered by registrars that substituted the registrar's own contact details for the registrant's personal information. The situation was only substantially resolved when GDPR forced registrars to redact personal data by default for European registrants in 2018, a change that was rapidly applied globally for practical compliance reasons.

The 'who is' phrasing was not accidental — the protocol was explicitly designed to answer the question 'who is responsible for this network resource?' in plain English. That design philosophy meant the protocol had no query syntax, no field names in requests, and no standardised response format, which is why WHOIS parsers have always been fragile. The successor protocol RDAP was designed precisely to address these limitations, returning machine-readable JSON with standardised fields, but as of the mid-2020s WHOIS is still the most widely used lookup method due to decades of tooling built around it.

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