What is RDAP?

The Registration Data Access Protocol, the JSON-over-HTTPS successor to WHOIS.

RDAP (RFC 9082/9083) returns domain registration data as structured JSON: registrar, registration and expiry dates, status codes, name servers and DNSSEC state. Every registry publishes its RDAP server in the IANA bootstrap file.

Since January 2025 ICANN treats RDAP as the authoritative source for generic top-level domains, so tools are moving from WHOIS text parsing to RDAP.

Try it

• RDAP lookup tool
• RDAP API

Related terms

• WHOIS: The original plain-text protocol (port 43) for looking up who registered a domain.
• DNS: The Domain Name System, which maps names like example.com to IP addresses and other records.