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When we register in TMDb, we must determine a Default Language and a Secondary Language.
In the dropdown of languages we have 292 options, including "none".
I believe the list of languages is based on the ISO 639-1 table.
https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes
And the list of countries is based on the ISO 3166-1 or ISO 3166-2 table.
https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2
https://en.wikipedia.org/wiki/ISO_3166-2
The code should be: language code ISO 639-1 - COUNTRY CODE ISO 3166-1 or 2.
es-ES, es-MX, pt-BR, hi-IN, etc...
I assume all are valid for entering movie data.
This needs to be confirmed by a Moderator.

Hi @yveslym4,

Assuming you're looking for this from a data perspective (API), you can find the following lists useful:

• Languages: https://developers.themoviedb.org/3/configuration/get-languages
• Countries: https://developers.themoviedb.org/3/configuration/get-countries
• Primary translations: https://developers.themoviedb.org/3/configuration/get-primary-translations

Could I request you to use the ISO 639-3 list instead of the ISO 639-1 list? I tried to add a Dagbani film today, but Dagbani (with more than 1 million native speakers in Ghana) is not listed in ISO 639-1.

I'd love to update the ISO codes but any changes to existing data would break the thousands of apps using TMDb. Because of this, migrating ISO's is a particularly tricky thing to do and not something I have time to look at in the near of future.

Same here guys, there are tens if not hundreds (I'm sure hundreds) of Amazigh(north africa's native languag)* films yet we always have to tag them as Arabic just for the the cultural interchange... films that participate in big festivals and checking what tmdb has to say.. yea it's arabic, which is not accurate. I hope you update to iso639-3 or do what's necessary to include this language. Thanks.