| 1738 | Uniform Resource Locators (URL)T. Berners-Lee, L. Masinter, M. McCahill · obsoleted by RFC 4248, RFC 4266 | Proposed Standard | December 1994 |
| 2045 | Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message BodiesN. Freed, N. Borenstein | Draft Standard | November 1996 |
| 2046 | Multipurpose Internet Mail Extensions (MIME) Part Two: Media TypesN. Freed, N. Borenstein | Draft Standard | November 1996 |
| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 2397 | The "data" URL schemeL. Masinter | Proposed Standard | August 1998 |
| 2425 | A MIME Content-Type for Directory InformationT. Howes, M. Smith, F. Dawson · obsoleted by RFC 6350 | Proposed Standard | September 1998 |
| 2426 | vCard MIME Directory ProfileF. Dawson, T. Howes · obsoleted by RFC 6350 | Proposed Standard | September 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 |
| 2739 | Calendar Attributes for vCard and LDAPT. Small, D. Hennessy, F. Dawson | Proposed Standard | January 2000 |
| 3282 | Content Language HeadersH. Alvestrand | Draft Standard | May 2002 |
| 3406 | Uniform Resource Names (URN) Namespace Definition MechanismsL. Daigle, D. van Gulik, R. Iannella, P. Faltstrom · obsoleted by RFC 8141 | Best Current Practice | October 2002 |
| 3536 | Terminology Used in Internationalization in the IETFP. Hoffman · obsoleted by RFC 6365 | Informational | May 2003 |
| 3629 | UTF-8, a transformation format of ISO 10646F. Yergeau | Internet Standard | November 2003 |
| 3966 | The tel URI for Telephone NumbersH. Schulzrinne | Proposed Standard | December 2004 |
| 3986 | Uniform Resource Identifier (URI): Generic SyntaxT. Berners-Lee, R. Fielding, L. Masinter | Internet Standard | January 2005 |
| 4122 | A Universally Unique IDentifier (UUID) URN NamespaceP. Leach, M. Mealling, R. Salz · obsoleted by RFC 9562 | Proposed Standard | July 2005 |
| 4288 | Media Type Specifications and Registration ProceduresN. Freed, J. Klensin · obsoleted by RFC 6838 | Best Current Practice | December 2005 |
| 4770 | vCard Extensions for Instant Messaging (IM)C. Jennings, J. Reschke, Ed. · obsoleted by RFC 6350 | Proposed Standard | January 2007 |
| 4880 | OpenPGP Message FormatJ. Callas, L. Donnerhacke, H. Finney, D. Shaw, R. Thayer · obsoleted by RFC 9580 | Proposed Standard | November 2007 |
| 5234 | Augmented BNF for Syntax Specifications: ABNFD. Crocker, Ed., P. Overell | Internet Standard | January 2008 |
| 5322 | Internet Message FormatP. Resnick, Ed. | Draft Standard | October 2008 |
| 5545 | Internet Calendaring and Scheduling Core Object Specification (iCalendar)B. Desruisseaux, Ed. | Proposed Standard | September 2009 |
| 5546 | iCalendar Transport-Independent Interoperability Protocol (iTIP)C. Daboo, Ed. | Proposed Standard | December 2009 |
| 5646 | Tags for Identifying LanguagesA. Phillips, Ed., M. Davis, Ed. | Best Current Practice | September 2009 |
| 5741 | RFC Streams, Headers, and BoilerplatesL. Daigle, Ed., O. Kolkman, Ed., IAB · obsoleted by RFC 7841 | Informational | December 2009 |
| 5751 | Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.2 Message SpecificationB. Ramsdell, S. Turner · obsoleted by RFC 8551 | Proposed Standard | January 2010 |
| 5870 | A Uniform Resource Identifier for Geographic Locations ('geo' URI)A. Mayrhofer, C. Spanring | Proposed Standard | June 2010 |
| 6068 | The 'mailto' URI SchemeM. Duerst, L. Masinter, J. Zawinski | Proposed Standard | October 2010 |
| 6351 | xCard: vCard XML RepresentationS. Perreault | Proposed Standard | August 2011 |