Free RDAP Check Tool

Everything you need to know about RDAP

Frequently Asked Questions

What is RDAP?

RDAP (Registration Data Access Protocol) is the modern, standardised protocol for querying domain registration data. Developed by ICANN and defined in RFC 7483, RDAP was designed to replace the ageing WHOIS protocol with a more structured, secure, and consistent approach to accessing domain registration information. Unlike WHOIS, which returns plain text in varying formats, RDAP returns machine-readable JSON responses with a consistent structure across all registrars and registries.

How is RDAP different from WHOIS?

RDAP improves on WHOIS in several important ways. It uses HTTPS for secure data transport, whereas WHOIS transmits over plain TCP. RDAP responses use a standardised JSON format, making them far easier to parse programmatically than the inconsistent plain-text output of WHOIS. RDAP also supports authentication, which allows credentialed users to access fuller registration data that might otherwise be redacted under GDPR. Finally, RDAP supports internationalised domain names (IDNs) more reliably than WHOIS.

What data does an RDAP lookup return?

An RDAP response includes structured data about the domain's registration: the domain name and its status codes, the registrar and registration dates (created, updated, expiry), the nameservers currently delegated to the domain, and contact entity information (which may be partially redacted under GDPR or local privacy regulations). It also includes links to the authoritative RDAP server and conformance data describing the RDAP response version.

Why was RDAP created to replace WHOIS?

WHOIS was developed in the early days of the internet and has significant limitations: it has no standard response format, no built-in security, no support for authentication or access control, and was not designed for an era of privacy legislation. As the internet scaled and GDPR came into effect, WHOIS's inability to handle tiered access to personal data became a critical problem. RDAP was built from the ground up to address these shortcomings and is now mandated by ICANN for all generic top-level domain (gTLD) registries.

Can I use RDAP to check any domain?

RDAP is supported by all ICANN-accredited registries for generic top-level domains (gTLDs) such as .com, .net, .org, .io, and most newer extensions. Country-code top-level domains (ccTLDs) such as .uk, .de, or .fr vary in their RDAP support — some have implemented it fully, while others still rely on WHOIS. For ccTLDs without RDAP support, a WHOIS fallback is typically used. Our tool will automatically query the correct protocol for the domain extension you enter.

How can RDAP help with domain security monitoring?

Regularly querying RDAP data for your domains lets you detect unexpected changes that could indicate a security incident: nameserver modifications that might redirect your traffic, registrar transfers you didn't authorise, or expiry dates creeping closer than expected. Automated RDAP monitoring — as part of a broader domain monitoring strategy — can alert you the moment any of these critical registration fields change, giving you time to respond before an attack or accidental lapse causes damage.

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Free RDAP test

Everything you need to know about RDAP

What is RDAP?

How is RDAP different from WHOIS?

What data does an RDAP lookup return?

Why was RDAP created to replace WHOIS?

Can I use RDAP to check any domain?

How can RDAP help with domain security monitoring?

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Uptime Monitoring

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Critical User Journey Monitoring