📇 Looking Up Domain Info With WHOIS/RDAP

Who registered it, when, and when it expires.

Here's how to check who registered a domain, when, and when it's set to expire.

Classic WHOIS vs. modern RDAP

Traditional WHOIS returned plain text in a format that varied by registry. RDAP (Registration Data Access Protocol) is the modern, standardized protocol that responds with structured JSON instead.

What you can find out

You can see the registrar, registration and expiration dates, nameservers, and domain status codes (EPP status). Since GDPR took effect in 2018, though, most individual registrants' names and emails are redacted.

Common use cases

This is useful for checking whether a domain is already registered before buying it, tracking the expiration date of a domain you own (missing a renewal risks losing it), and checking how recently a suspicious site's domain was registered — newly registered domains tend to carry higher phishing risk.

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