Registration data from public RDAP services

RDAP Lookup for Domains, IP Addresses, and ASNs

Trace an internet resource to the RDAP service selected through IANA bootstrap data.

What this is

Registration data, without the middleman.

RDAP Lookup uses IANA's public bootstrap registries to find the authoritative operator for a resource. Queries run from your browser to that operator.

Reading room

Protocol notes

All guides

Sep 2026

Why an RDAP Lookup Fails in a Browser

Learn why a browser-based RDAP lookup can fail because of CORS, endpoint errors, redirects, rate limits or invalid responses, and how to identify the failure without mistaking it for missing registration data.

Sep 2026

How to Find an Abuse Contact for an IP Address with RDAP

Use an IP address RDAP response to find the appropriate abuse contact, understand nested entities, and prepare an evidence-based report without mistaking registration data for attribution.

Sep 2026

How to Read an ASN RDAP Response

Learn how to read an ASN RDAP response, including autnum ranges, registration status, entities, RIR data and the limits of routing attribution.