.arpa Domain WHOIS & RDAP Lookup
.arpa is the infrastructure top-level domain. It is managed by IANA and used for technical purposes such as reverse DNS lookups under in-addr.arpa and ip6.arpa, not for ordinary domain registrations.
.arpa TLD facts
| Property | Value |
|---|---|
| TLD | .arpa |
| Type | Infrastructure TLD |
| Status | Active |
| WHOIS server | whois.iana.orgAll 2 TLDs using whois.iana.org |
| RDAP endpoint | Not published |
| IANA record updated | |
| IANA record | .arpa in the IANA root zone database |
How to look up a .arpa domain
The quickest way is to type the domain into the search box above: W.is queries the .arpa registry and shows the result in a readable format. You can also query the registry yourself from a terminal.
WHOIS lookup
The .arpa WHOIS server listed by IANA is whois.iana.org. WHOIS (RFC 3912) is the older plain-text protocol on TCP port 43:
whois -h whois.iana.org example.arpaWhich protocol does W.is use?
IANA's data lists no RDAP service for .arpa, so W.is looks up .arpa domains over WHOIS and turns the plain-text response into the same readable format.
New to the protocols? Read what RDAP is and how it compares in RDAP vs WHOIS.
Other TLDs using whois.iana.org
The WHOIS server whois.iana.org answers for 2 TLDs, including .arpa. The other one is:
Frequently asked questions
What is the WHOIS server for .arpa?
The WHOIS server for .arpa is whois.iana.org, as listed in the IANA root zone database. It answers queries on TCP port 43 (for example, whois -h whois.iana.org example.arpa).
Does .arpa support RDAP?
Not in IANA's RDAP bootstrap registry, which lists no RDAP service for .arpa, so W.is looks up .arpa domains over WHOIS instead. The registry may still run its own RDAP server outside that list.
Who manages .arpa domains?
.arpa names are assigned directly by IANA; there are no registrars. .arpa zones such as in-addr.arpa and ip6.arpa are delegated by IANA on behalf of the IAB.
Do .arpa domains expire?
No. .arpa delegations are not sold for a fixed term, so there is no public expiration date to renew.
Related resources
- Full list of top-level domains with their WHOIS and RDAP servers
- RDAP server list: every RDAP endpoint and the TLDs it serves
- WHOIS server list: port-43 WHOIS servers by TLD
- What is RDAP? An introduction to the protocol that is replacing WHOIS
- Domain status codes explained, such as clientTransferProhibited