RDAP domain lookup
Asks the registry's RDAP server from the IANA bootstrap file (RFC 9224) for the registrable domain and reports registrar, creation, change and expiry dates, EPP statuses, nameservers and DNSSEC delegation. Contact data is never kept or returned.
Updated 2026-10-26
What this tool checks
The tool finds the registry's RDAP server for the domain's top-level domain in IANA's bootstrap file and asks it about the registrable domain, the name just below the public suffix (example.co.uk for www.example.co.uk). It reports:
- Registrar: the name and IANA registrar ID.
- Dates: when the domain was registered, last changed and when it expires, with the days until expiry. An expired registration is
DOMAIN_EXPIRED; less than 30 days left isDOMAIN_EXPIRING_SOON. - EPP status codes: in RDAP's spelling, such as
client transfer prohibited. A hold means the registry has taken the domain out of DNS (DOMAIN_ON_HOLD); redemption period and pending delete mean it is about to be released (DOMAIN_PENDING_DELETE). - Nameservers and DNSSEC: the delegated nameservers and whether the registry holds a DS record (
delegation_signed).
A domain the registry does not know gives DOMAIN_NOT_REGISTERED.
How to read the result
Expiry and the hold and delete statuses are the urgent cases, because the domain stops working or can be lost. A missing transfer lock is information. When the registry cannot be asked, the status is unknown rather than a guess.
For whether DNSSEC actually validates, use the DNSSEC check; RDAP only says whether the parent holds a DS record.
Limitations
- Only the registry's RDAP server is asked, not the registrar's, and WHOIS on port 43 is not used.
- Registries differ in what they publish; fields a registry leaves out are shown as empty.
- Contact data is never shown, even when the registry publishes it.
Use it from code
API reference for RDAP domain lookup
curl -i "https://api.lookproof.dev/v1/domain/rdap?domain=example.com"A request without payment is answered with 402 Payment Required and the exact price. See the API reference.
Limits
| Input | Domain |
|---|---|
| Deadline | 10 seconds |
| Freshness | Up to 5 minutes, never longer than the record TTL |
| Price | $0.01 per check |
Findings this tool can report
RDAP (1)
- Info
RDAP_UNAVAILABLEThe registry's RDAP service could not be asked about the domain.
Domain registration (6)
- Error
DOMAIN_EXPIREDThe domain registration has expired. - Warning
DOMAIN_EXPIRING_SOONThe domain registration expires in less than 30 days. - Info
DOMAIN_NOT_REGISTEREDThe registry has no record of the domain. - Error
DOMAIN_ON_HOLDThe domain is on hold and is not published in DNS. - Error
DOMAIN_PENDING_DELETEThe domain is about to be deleted. - Info
DOMAIN_TRANSFER_UNLOCKEDThe domain has no transfer lock.
Frequently asked questions
What is RDAP, and how is it different from WHOIS?
RDAP (Registration Data Access Protocol, RFC 9083) is the successor to WHOIS. It answers over HTTPS with structured JSON instead of free text, and IANA publishes which server is responsible for each top-level domain (RFC 9224). ICANN requires RDAP for generic top-level domains and stopped requiring WHOIS for them in January 2025. Some country-code domains still offer only WHOIS.
Why does the result not show who owns the domain?
Lookproof only reads the registrar from the registry's answer. Contact entities such as the registrant are thrown away before anything is shown or stored, even when the registry publishes them. The registrar, the dates and the status codes are enough to see whether a domain is about to lapse or is locked.
What does client transfer prohibited mean?
It is an EPP status (RFC 5731) that the registrar sets on request. While it is set, a transfer to another registrar is refused, which protects against hijacking. Without it the check reports DOMAIN_TRANSFER_UNLOCKED as information. Some registries do not use the status at all.
Why is the RDAP service unavailable for my domain?
Either the top-level domain has no RDAP server in IANA's bootstrap file, which is still the case for several country-code domains, or the registry's server did not answer properly. The reason is in the evidence of RDAP_UNAVAILABLE, and the result's status is unknown.