Information on ISO 639-3

What is ISO 639-3?

ISO 639-3 is a set of codes that defines three-letter identifiers for all known human languages. At the core of ISO 639-3 are the individual languages already accounted for in ISO 639-2. The large number of living languages in the initial inventory of ISO 639-3 beyond those already included in ISO 639-2 was derived primarily from Ethnologue (15th edition). Additional extinct, ancient, historic, and constructed languages were obtained from the Linguist List. For the criteria for a language to receive a code, read here.

Registration Authority

SIL International has been designated as the ISO 639-3/RA for the purpose of processing requests for alpha-3 language codes comprising the International Standard, Codes for the representation of names of languages - Part 3: Alpha-3 code for comprehensive coverage of languages. The ISO 639-3/RA receives and reviews applications for requesting new language codes and for the change of existing ones according to criteria indicated in the standard. It maintains an accurate list of information associated with registered language codes which can be viewed on or downloaded from this website, and processes updates of registered language codes. Notifications of pending and adopted updates are also distributed on a regular basis to subscribers and other parties.


This is the official site of the ISO 639-3 Registration Authority and thus is the only one authorized by ISO. If you have questions concerning ISO 639-3 please contact us at:

SIL International
​ISO 639-3 Registrar
7500 W. Camp Wisdom Road
Dallas, TX  75236

​Phone: +1 972 708 7400 x2100