.arpa
.arpa is an infrastructure extension, run by Internet Architecture Board (IAB). .arpa is reserved for internet infrastructure, so there are no public registrations.
| Type | Infrastructure |
|---|---|
| Registry operator | Internet Architecture Board (IAB) |
| Who can register | No registrations Reserved for internet infrastructure; no public registrations. |
| DNSSEC | Signed |
| RDAP server | None listed |
| WHOIS server | whois.iana.org |
| IANA record | iana.org/domains/root/db/arpa |
New to extensions? The guide to how domain extensions work covers generic, country-code and brand extensions. For who sells extensions in general, see the list of domain registrars.
Sources: the IANA root zone database and the ICANN list of generic extensions (refreshed 2026-10-24). Something out of date? Tell us.
Frequently asked questions
Who runs the .arpa extension?
Internet Architecture Board (IAB) is the registry operator for .arpa. The registry keeps the list of every .arpa name; registrars sell the names to the public.
Can anyone register a .arpa domain?
.arpa is reserved for internet infrastructure, so there are no public registrations.
How do I look up who owns a .arpa domain?
The .arpa registry publishes registration data over WHOIS at whois.iana.org. The free domain report on lemon.domains reads it for you and shows the registrar, dates and status.
Is .arpa signed with DNSSEC?
Yes. The .arpa zone is signed, so a .arpa domain can turn on DNSSEC once its registrar adds a DS record.