What Is RDAP? The Modern Replacement for WHOIS Domain Lookup

WHOIS Is Being Retired

For over 40 years, WHOIS has been the protocol for looking up domain registration information. Type "whois example.com" and you'd see who registered it, when, and how to contact them. But WHOIS was designed in a pre-internet era and is being replaced by RDAP — the Registration Data Access Protocol.

What Is RDAP?

RDAP (Registration Data Access Protocol) is a modern, standardized protocol for accessing domain name registration data. It was developed by the IETF (Internet Engineering Task Force) to address the shortcomings of WHOIS.

Think of RDAP as WHOIS 2.0 — same basic function (looking up domain info), but with modern architecture, security, and privacy features.

How RDAP Differs From WHOIS

Structured Data

WHOIS returns plain text that's formatted differently by every registrar. Parsing it programmatically is a nightmare. RDAP returns structured JSON data with consistent formatting, making it easy to process automatically.

Built-In Privacy

WHOIS was designed before internet privacy was a concern. All data was public by default. RDAP has access control built into the protocol — registrars can restrict sensitive information based on who's asking and why.

Authenticated Access

WHOIS has no concept of user authentication. Anyone can query anything. RDAP supports authentication, allowing registrars to provide different levels of data access to different types of requesters (law enforcement vs general public).

Internationalization

WHOIS struggles with non-ASCII characters. RDAP natively supports Unicode, making it work properly with internationalized domain names and contact information in non-Latin scripts.

Standardized Responses

Every registrar's WHOIS output looks different. RDAP responses follow a standard format defined in RFCs 7480-7484, making it possible to build tools that work consistently across all registrars.

What RDAP Shows

An RDAP lookup typically returns:

Domain name and registration status
Registrar name and contact information
Registration dates (created, updated, expires)
Name servers associated with the domain
DNSSEC status
Registrant information (may be redacted for privacy)
Abuse contact information

The exact fields visible depend on the registrar's privacy policy and whether you're authenticated.

How to Use RDAP

Web-Based Lookup

Several websites offer RDAP lookups:

rdap.org
Registration data lookup tools built into registrar websites
ICANN's RDAP lookup tool

Command Line

curl https://rdap.verisign.com/com/v1/domain/example.com

Programmatic Access

RDAP's JSON responses make it ideal for integration into applications, monitoring tools, and automated workflows.

What RDAP Means for Domain Owners

Better Privacy by Default

Under RDAP, your personal registration data is more protected. Registrars are implementing tiered access — casual lookups see limited info, while verified parties (law enforcement, IP holders) can request more.

No Action Required

The transition from WHOIS to RDAP happens at the registrar and registry level. Domain owners don't need to do anything — your domain registration data is automatically served via RDAP.

Privacy Protection Still Matters

While RDAP has better privacy features than WHOIS, registrars still vary in how they implement access controls. Enabling domain privacy protection through your registrar remains good practice.

What RDAP Means for Brand Protection

If you're monitoring for trademark infringement or domain squatting:

RDAP makes automated monitoring more reliable (structured data)
But privacy protections make it harder to identify domain registrants
You may need to file formal requests to unmask registrant data
Law enforcement and trademark holders can request authenticated access

The Transition Timeline

2015-2019: RDAP specification finalized and early adoption
2019-2023: ICANN mandated RDAP support for gTLD registries and registrars
2024-2026: WHOIS being phased out; RDAP becoming the primary protocol
2027+: Expected full deprecation of WHOIS for gTLDs

Some ccTLDs are transitioning at their own pace.

Practical Takeaways

RDAP is not something you need to "switch to" — it happens automatically
Your privacy settings still matter — enable domain privacy at your registrar
If you build tools that query domain data, migrate from WHOIS to RDAP APIs
Brand monitoring tools should support RDAP for more reliable data

Protect Your Brand Across All Channels

Domain lookup tools like RDAP help you research existing domains. But for checking whether your brand name is available across domains, social media, and trademarks, use BrandScout — one search covers all the platforms your brand needs.