WHOIS
DomainsWHOIS is a query and response system that lets you look up registration details for a domain name or IP address block, such as the registrar, registration and expiration dates, name servers, and contact or proxy information. It is used to verify ownership, troubleshoot DNS and transfer issues, and assess the legitimacy of a domain, subject to privacy and policy restrictions.
How It Works
WHOIS works by sending a lookup request for a domain name (or IP range) to a WHOIS service, which returns the registration record associated with that resource. For domains, the query typically starts at the top-level domain (TLD) registry (for example, .com or .net). The registry response often points to the authoritative WHOIS server at the registrar, where the detailed record is maintained and returned.
A WHOIS record commonly includes the registrar name, registry status codes (such as clientTransferProhibited), creation and expiration dates, and the domain's name servers. Registrant, administrative, and technical contact fields may be redacted or replaced with a privacy or proxy service, depending on registry rules and data-protection policies. Many systems also provide a web-based lookup, while some administrators use command-line tools or APIs for automation and monitoring.
Why It Matters for Web Hosting
When choosing hosting or managing a site move, WHOIS helps confirm where a domain is registered, whether it is eligible for transfer, and which name servers currently control DNS. It can reveal whether a domain is close to expiration, locked against transfer, or using a privacy service that may affect verification emails. For troubleshooting, WHOIS complements DNS checks by showing the registrar side of domain control, which is often the deciding factor in resolving propagation, transfer, and ownership disputes.
Common Use Cases
- Verifying the registrar and name servers before changing DNS or pointing a domain to a new host
- Checking domain expiration and renewal status to avoid downtime caused by an expired registration
- Confirming transfer readiness by reviewing lock status and other registry status codes
- Investigating suspicious domains by reviewing registration dates, registrar, and privacy/proxy indicators
- Finding the correct abuse or administrative contact channel when dealing with phishing, spam, or trademark issues
- Auditing domain portfolios to ensure records match expected ownership and management details
WHOIS vs DNS Lookup
WHOIS shows registration and control information (who manages the domain at the registrar/registry level and key dates), while a DNS lookup shows how the domain currently resolves (A/AAAA, CNAME, MX, TXT records) and where traffic is directed. If a site is not loading, DNS answers explain the current routing, but WHOIS can reveal whether the domain is expired, locked, or delegated to unexpected name servers, which can prevent DNS changes from taking effect.