A special-use domain name is a domain name that is defined and reserved in the hierarchy of the Domain Name System of the Internet for special purposes. The designation of a reserved special-use domain is authorized by the Internet Engineering Task Force (IETF) and executed, maintained, and published by the Internet Assigned Numbers Authority (IANA).
Reserved domain names
The following list comprises the domain names list by IANA in the category of special-use domain names.
| Domain | Purpose | Authority document |
|---|---|---|
| alt. | preventing name collisions with DNS | RFC 9476 |
| 6tisch.arpa. | IETF 6TiSCH working group | RFC 9031 |
| 10.in-addr.arpa. | private network reverse mapping | RFC 6761 |
| 16.172.in-addr.arpa. | ||
| 17.172.in-addr.arpa. | ||
| 18.172.in-addr.arpa. | ||
| 19.172.in-addr.arpa. | ||
| 20.172.in-addr.arpa. | ||
| 21.172.in-addr.arpa. | ||
| 22.172.in-addr.arpa. | ||
| 23.172.in-addr.arpa. | ||
| 24.172.in-addr.arpa. | ||
| 25.172.in-addr.arpa. | ||
| 26.172.in-addr.arpa. | ||
| 27.172.in-addr.arpa. | ||
| 28.172.in-addr.arpa. | ||
| 29.172.in-addr.arpa. | ||
| 30.172.in-addr.arpa. | ||
| 31.172.in-addr.arpa. | ||
| 168.192.in-addr.arpa. | ||
| 170.0.0.192.in-addr.arpa. | NAT64 prefix discovery (RFC 7050) | RFC 8880 |
| 171.0.0.192.in-addr.arpa. | ||
| ipv4only.arpa. | ||
| 254.169.in-addr.arpa. | Use in multicast DNS (mDNS) | RFC 6762 |
| 8.e.f.ip6.arpa. | ||
| 9.e.f.ip6.arpa. | ||
| a.e.f.ip6.arpa. | ||
| b.e.f.ip6.arpa. | ||
| home.arpa. | Non-unique use on residential networks | RFC 8375 |
| example. | documentation, tutorials, etc. | RFC 6761 |
| example.com. | use in documentation, tutorials, testing | RFC 6761 |
| example.net. | ||
| example.org. | ||
| invalid. | Avoidance of confusion and errors per RFC 2606 | RFC 6761 |
| local. | Used for Multicast DNS | RFC 6762 (Section 3) |
| localhost. | Reserved to avoidance of confusion and errors | RFC 6761 |
| onion. | Anonymous onion service | RFC 7686 |
| test. | Avoidance of confusion, allowing use for documentation and network testing | RFC 6761 |
See also
References
- RFC 6761, S. Chesire, M. Krochmal, Special-Use Domain Names, IETF (February 2013)
- "Special-Use Domain Names". Internet Assigned Number Authority. Retrieved 2020-06-16.