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                                                      Language Subtags, Tag Extensions, and Tags

Last Updated
        2025-04-02

Available Formats
        [IMG]
        XML [IMG]
        HTML [IMG]
        TXT

Registries Included Below

  • Language Subtag Registry
  • Language Tag Extensions
  • Language Tags (OBSOLETE)

Language Subtag Registry

Registration Procedure(s)

             Expert Review


Expert(s)

             Doug Ewell


Reference
        [RFC 5645][RFC 5646]

Note

 Registration requests should be submitted to the
 [ietf-languages@ietf.org] mailing list. For more information, see
 [RFC 5646, Section 3.5].


Note

 The format of the registry is explained in Section 3 and [Section 3.1 of RFC 5646].

 When referring to language tags in specifications, please refer to
 [RFC 5646].


Registry File


 [Language Subtag Registry]


Supplemental Information


 Language subtag registration forms are available in the [Language
 Subtag Registration Form Archive.]


Language Tag Extensions

Registration Procedure(s)

             IETF Review or IESG Approval


Reference
        [RFC 5646]

Note

 While registration requires IESG approval or an IETF Stream RFC, the
 maintaining authority for an extension can submit changes to contact
 information and/or URLs directly to IANA, as described in [RFC 5646, Section 5.2].


Registry File


 [Language Tag Extensions Registry]


Language Tags (OBSOLETE)

Registration Procedure(s)

             Registry closed


Reference
        [RFC 3066][RFC 4646]

Note

 This registry is obsolete and has been replaced by the [Language
 Subtag Registry], as described in [RFC 4646, Section 5.1].


Registry File


 [Language Tags (OBSOLETE)]


Supplemental Information


 Language tag registration forms are available in the [Language Tag
 Registration Form Archive].


Licensing Terms