How to add 2 letter language code in ISO 639-1

Doug Ewell doug at
Tue Feb 28 16:37:17 CET 2017

Saroj <sarojchakma20 at gmail dot com> wrote:

> Hi, I want to know how to add Chakma Language in two letter code. We
> have 3 letter code in ISO 639-3 as ccp.

According to the ISO 639 Joint Advisory Committee [1]:

"A language code already in ISO 639-2 at the point of freezing ISO 639-1
shall not later be added to ISO 639-1. This is to ensure consistency in
usage over time, since users are directed in Internet applications to
employ the alpha-3 code when an alpha-2 code for that language is not

Even if such a code element were added to ISO 639-1, it would not be
added to the IANA Language Subtag Registry. According to RFC 5646 [2]:

"In order to avoid instability in the canonical form of tags, if a
two-character code is added to ISO 639-1 for a language for which a
three-character code was already included in either ISO 639-2 or ISO
639-3, the two-character code MUST NOT be registered."


"Codes assigned by ISO 639-1 that do not conflict with existing
two-letter primary language subtags *and that have no corresponding
three-letter primary defined in the registry* are entered into the IANA
registry as new records of type 'language'." [emphasis added]

Doug Ewell | Thornton, CO, US |

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