WHOIS is the legacy registration lookup protocol. It returns plain-text records for domain names and IP allocations, but output format differs by registry and is often inconsistent.

RDAP / WHOIS Lookup

Q: What is RDAP?

RDAP (Registration Data Access Protocol) is the modern successor to WHOIS. It returns structured JSON with standardized fields for entities, statuses, events, nameservers, and network ranges.

Look up registration data for any domain or IP address. We query RDAP first, then fallback to WHOIS when needed.

What This Tool Does

This RDAP / WHOIS Lookup retrieves registration records for domains and IP addresses. It helps you identify who manages a domain or network block, when records were created or updated, and which statuses or nameservers are currently published.

What Is WHOIS?

WHOIS is the older lookup system used by registries and registrars to publish registration details. WHOIS output is plain text and each registry formats fields differently, which makes parsing less predictable.

What Is RDAP?

RDAP (Registration Data Access Protocol) is the modern replacement for WHOIS. It provides structured JSON with standardized fields such as entities, events, statuses, nameservers, and network range data, making results easier to process reliably.

How This Tool Uses RDAP and WHOIS

The tool queries RDAP first because it is cleaner and more consistent. If RDAP is unavailable or incomplete for a registry, it automatically falls back to WHOIS to maximize coverage.

Common Use Cases

Check domain registrar, registration dates, and expiration windows.
Audit nameserver and domain status changes during incidents.
Investigate IP range ownership and registry metadata.
Cross-check registration data while triaging abuse reports.

Related Tools & Guides

IP Lookup - geolocation, ASN, and risk profile for any IP.
Forward DNS Lookup - resolve domain A, AAAA, MX, TXT, NS records.
Reverse DNS Lookup - map IP addresses to PTR hostnames.
CT Monitor - inspect certificate issuance history for domains.

Frequently Asked Questions

What is WHOIS?

WHOIS is the legacy registration lookup protocol. It returns plain-text records for domains and IP allocations, but field formatting depends on each registry.

What is RDAP?

RDAP is the modern successor to WHOIS. It returns structured JSON with standardized keys for common data like statuses, registrar entities, dates, nameservers, and network ranges.

Can I look up both domains and IP addresses?

Yes. This tool accepts both domain names and IPv4 or IPv6 addresses in a single search field.

Why does the tool sometimes use WHOIS fallback?

If an RDAP endpoint does not return usable data, the tool runs a WHOIS fallback query to improve coverage across registries.