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, historic, and constructed languages were obtained from the Linguist List.

Language Coding Agency

SIL International functions as the Language Coding Agency for Set 3 of the ISO 639 language code standard under ISO639/MA-ToR, the Terms of Reference for the ISO 639 Maintenance Agency.  SIL is responsible for receiving and registering Change Requests unique to language identifiers in Set 3 of ISO639:2023, Code for individual languages and language groups. The ISO 639-3/LCA 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 or downloaded from this website, and processes updates of registered language codes.

This is the official site of the ISO 639-3 Language Coding Agency.

Contact us:

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

Email: [email protected]
​Phone: +1 972 708 7400 x2420