| 1766 | Tags for the Identification of LanguagesH. Alvestrand · obsoleted by RFC 3066, RFC 3282 | Proposed Standard | March 1995 |
| 2026 | The Internet Standards Process -- Revision 3S. Bradner | Best Current Practice | October 1996 |
| 2028 | The Organizations Involved in the IETF Standards ProcessR. Hovey, S. Bradner · obsoleted by RFC 9281 | Best Current Practice | October 1996 |
| 2046 | Multipurpose Internet Mail Extensions (MIME) Part Two: Media TypesN. Freed, N. Borenstein | Draft Standard | November 1996 |
| 2047 | MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII TextK. Moore | Draft Standard | November 1996 |
| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 2231 | MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and ContinuationsN. Freed, K. Moore | Proposed Standard | November 1997 |
| 2277 | IETF Policy on Character Sets and LanguagesH. Alvestrand | Best Current Practice | January 1998 |
| 2616 | Hypertext Transfer Protocol -- HTTP/1.1R. Fielding, J. Gettys, J. Mogul, H. Frystyk, L. Masinter, P. Leach, T. Berners-Lee · obsoleted by RFC 7230, RFC 7231, RFC 7232, RFC 7233, RFC 7234, RFC 7235 | Draft Standard | June 1999 |
| 2781 | UTF-16, an encoding of ISO 10646P. Hoffman, F. Yergeau | Informational | February 2000 |
| 3066 | Tags for the Identification of LanguagesH. Alvestrand · obsoleted by RFC 4646, RFC 4647 | Best Current Practice | January 2001 |
| 3282 | Content Language HeadersH. Alvestrand | Draft Standard | May 2002 |
| 3339 | Date and Time on the Internet: TimestampsG. Klyne, C. Newman | Proposed Standard | July 2002 |
| 3552 | Guidelines for Writing RFC Text on Security ConsiderationsE. Rescorla, B. Korver | Best Current Practice | July 2003 |
| 3629 | UTF-8, a transformation format of ISO 10646F. Yergeau | Internet Standard | November 2003 |
| 4645 | Initial Language Subtag RegistryD. Ewell | Informational | September 2006 |
| 4646 | Tags for Identifying LanguagesA. Phillips, M. Davis · obsoleted by RFC 5646 | Best Current Practice | September 2006 |
| 4647 | Matching of Language TagsA. Phillips, Ed., M. Davis, Ed. | Best Current Practice | September 2006 |
| 5226 | Guidelines for Writing an IANA Considerations Section in RFCsT. Narten, H. Alvestrand · obsoleted by RFC 8126 | Best Current Practice | May 2008 |
| 5234 | Augmented BNF for Syntax Specifications: ABNFD. Crocker, Ed., P. Overell | Internet Standard | January 2008 |
| 5645 | Update to the Language Subtag RegistryD. Ewell, Ed. | Informational | September 2009 |