The function of the Registry of Languages (ROL) within HIS is to provide standardized codes for identifying human languages used in the world today. Rather than devising its own system of codes, HIS makes use of the three-letter codes for identifying languages that have been defined and published according to the ISO 639 International Standard. This standard provides identifiers for Living, Extinct, Historical and Constructed languages. Find definitions used in the standard for concepts involved, particularly the definition for an “Individual Language,” at https://iso639-3.sil.org/about/scope. Code tables are available at https://iso639-3.sil.org/code_tables/download_tables and include:

  • The ISO 639-3 Code Set (which includes the identifiers that correspond to Sets 1 and 2 of ISO 639)
  • The Language Name Index (the standard includes additional names used for the same language such as variant spellings or common exonyms)
  • The Macrolanguage Mappings (see https://iso639-3.sil.org/about/scope for an explanation)
  • The Retired Code Element Mappings (instruction for what to do when dealing with an identifier that has been retired)

In addition to the ISO 639-3 code set, definitions, and code history information, for living languages find additional descriptive information in the Ethnologue (29th edition as of February 2026; see https://www.ethnologue.com/).

Each three-letter code uniquely identifies one of the more than 7,100 living languages (and some extinct languages) in the standard that are documented in the Ethnologue. Any application that makes use of one of the living languages in the set is just one click away from access to language descriptions that are available in Ethnologue. That is, for any language identifier [abc] that may be stored in a database, an application may present a link to the following URL in order to give the user access to Ethnologue’s description of that language: https://ethnologue.com/language/abc. The ISO 639-3 standard as a whole has documentation for each identifier according to the pattern https://iso639-3.sil.org/code/abc, particularly code retirements and updates.

The definition used in the Ethnologue for identifying languages is based on a criterion of shared literature. If varieties of speech are similar enough to use the same literature, they are considered the same language; if they would need different literatures, they are considered different languages. Where there is no existing literature, a judgment as to whether literature might be shared is based on the presence of shared intelligibility and shared identity.

Each Ethnologue language page displays the ISO 639-3 code, which distinguishes the language from other languages with the same or similar names. Context can lead to different choices about name use, so Ethnologue identifies cases in which the name differs across country borders, ensuring that each language is counted only once in world or area statistics. Ethnologue language names may differ from the reference name included in the ISO 639-3 code element at https://iso639-3.sil.org/.

The Ethnologue code set (with documentation) may be downloaded from: http://www.ethnologue.com/codes. Tables in this set contain additional data, including a larger set of additional language names and the relationships between language and country in which the language has an established population of users.

Any party is welcome to incorporate the download tables into its own database application on condition that it is done in accordance with the ISO 639-3 Terms of Use and/or the Ethnologue’s Terms of Use Statement (depending on which tables are used).

Change history for any identifier can be found at its identifier documentation page, for example: https://iso639-3.sil.org/code/yol (retired in 2025), including name changes and denotation changes. Users may subscribe to the quarterly newsletter of the ISO 639 Maintenance Agency distributed by SIL to be notified of new and retired codes as well as updates to names and denotation.

Last modified: July 2026

ROL Documents