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WHOIS Lookup Guide: Domain Registration Data Explained

Learn what WHOIS is, what data it contains, how to do a WHOIS lookup, and how GDPR privacy affects domain registration data.

Table of Contents

  1. What Is WHOIS?
  2. What WHOIS Data Contains
  3. How to Do a WHOIS Lookup
  4. WHOIS Privacy Protection
  5. WHOIS vs RDAP
  6. FAQ

What Is WHOIS?

WHOIS is a query protocol used to look up registration information for domain names and IP addresses. Created in the early 1980s, it lets anyone find who registered a domain, when it was registered, when it expires, and who the registrar is.

What WHOIS Data Contains

FieldExampleMeaning
RegistrarGoDaddy, NamecheapCompany that sold the domain
RegistrantJohn Doe / Privacy ProxyDomain owner
Created Date2010-03-15When domain was first registered
Updated Date2025-01-10Last modification date
Expiry Date2027-03-15When registration expires
Name Serversns1.example.comDNS servers for the domain
StatusclientTransferProhibitedDomain lock status

How to Do a WHOIS Lookup

The easiest way is NetTool1 WHOIS Lookup — enter any domain and get structured results instantly. Command line:

whois example.com
whois 8.8.8.8

Domain age matters for SEO: Use Domain Age Checker to verify how long a domain has been registered — older domains typically carry more authority.

WHOIS Privacy Protection

GDPR (2018) dramatically reduced public WHOIS data for .com/.net domains. Most registrars now offer free privacy protection that replaces your contact details with a proxy service. Despite this, you can still see:

WHOIS vs RDAP

RDAP (Registration Data Access Protocol) is the modern replacement for WHOIS. It returns structured JSON instead of plain text and supports authentication for accessing redacted data.

FeatureWHOISRDAP
FormatPlain textJSON
Port43443 (HTTPS)
InternationalizationLimitedFull Unicode
AuthenticationNoneSupported

FAQ

Can I find the owner of a private domain?
If privacy protection is enabled, you see proxy details. You can contact the registrar or use legal channels for legitimate business reasons, but there is no public method to bypass privacy protection.
How do I check if a domain is expiring soon?
Look at the Expiry Date in WHOIS results. Domains expiring within 30 days are at risk of dropping. Set a calendar reminder if you own domains you want to keep.
What do domain status codes mean?
clientTransferProhibited means the domain is locked against registrar transfers. clientHold means it is suspended. ok or active means the domain is in normal operation.