WHOIS Lookup
Registration data for any domain or IP block, fetched via RDAP — the modern HTTPS-based replacement for WHOIS.
What is WHOIS?
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A protocol for asking who registered something.
WHOIS is a query/response protocol used to look up the registered owners of a domain name, IP address block, or autonomous system. The data includes registrar, registration and expiration dates, name servers, and (sometimes redacted) contact info.
This tool uses RDAP (Registration Data Access Protocol), the modern HTTPS-based replacement for WHOIS. Queries are routed via rdap.org to the registrar or registry's own RDAP server. Responses are returned as structured JSON. Most TLDs and IP regional registries support RDAP today.