ISO 639-1:2002, Codes for the representation of names of languages—Part 1: Alpha-2 code, is the first part of the ISO 639 series of international standards for language codes. Part 1 covers the registration of "set 1" two-letter codes. There are 183 two-letter codes registered as of June 2021. The registered codes cover the world's major languages.

Infoterm (International Information Centre for Terminology) is the registration authority for ISO 639-1 codes.

These codes are a useful international and formal shorthand for indicating languages.

<!--Please do not add additional examples unless they demonstrate a pattern not already shown in the table and it has been discussed on the talk page-->

{| class="wikitable" style="text-align:center; margin: 1em auto 1em auto"

|+ Examples of ISO 639-1 codes

|-

! rowspan="2" | Code !! ISO 639-1 language name !! rowspan="2" | Endonym

|-

!English

|-

| <code>en</code> || English || English<!--Example of a code using two consecutive letters of the English language name-->

|-

| <code>es</code> || Spanish || <!--Example of a code using two consecutive letters of the endonym (as well as a non-English ISO 639-1 language name)-->

|-

| <code>pt</code> || Portuguese || <!--Example of a code using two nonconsecutive letters-->

|-

| <code>zh</code> || Chinese || , <!--Example of a code using letters from the transcription of an endonym-->

|}

ISO 639-1 is more restrictive than other ISO 639 parts, such as ISO 639-2 and ISO 639-3, which cover a wider range of languages and variations.

Many multilingual websites, including Wikipedia, use these codes to prefix URLs of localised versions: for example, <code>ja.wikipedia.org</code> is the Japanese version of Wikipedia.

History

ISO 639, the original standard for language codes, was approved in 1967. It was designed to represent major and primary national languages with well-established terminologies and lexicography.

In 1998 the standard was extended with an additional part, ISO 639-2, providing three-letter codes for a much wider range of languages.

The original standard was redesignated as ISO 639-1 in 2002, in an updated version.

Updates

New ISO 639-1 codes are not added if an ISO 639-2 "set 2" three-letter code exists, so systems that use ISO 639-1 and 639-2 codes, with 639-1 codes preferred, do not have to change existing codes.

If an ISO 639-2 code that covers a group of languages is used, it might be overridden for some specific languages by a new ISO 639-1 code.

Part 3 (2007) of the standard, ISO 639-3, aiming to cover all known natural languages, largely supersedes the ISO 639-2 three-letter code standard.

There is no specification on treatment of macrolanguages, which are covered by ISO 639-3.

IETF language tags

The use of ISO 639 language codes was encouraged by the introduction of IETF language tags via RFC&nbsp;1766 in March 1995. The current version of the specification is RFC&nbsp;5646 from September 2009.

See also

  • Lists of ISO 639 codes
  • ISO 3166-1 alpha-2, a different set of two-letter codes used for countries

References

  • ISO 639
  • ISO 639-1/RA