diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index 2eb598c726..63b61ba8a3 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -42,7 +42,7 @@ More details about each attribute:
 | ------------ | ---
 | tvg-id       | Channel ID that is used to load EPG. Must match `id` from the EPG file. (optional)
 | tvg-name     | Channel name that is also sometimes used to load EPG. Must match `display-name` from the EPG file. (optional)
-| tvg-language | Channel language. The name of the language must conform to the standard [ISO 639-1](https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes) (optional)
+| tvg-language | Channel language. The name of the language must conform to the standard [ISO 639-3](https://iso639-3.sil.org/code_tables/639/data) (optional)
 | tvg-logo     | The logo of the channel that will be displayed in the player if it supports it (optional)
 | group-title  | The category to which the channel belongs. These categories are also displayed in some players, and grouped playlists are also generated based on them. The list of currently supported categories can be found [here](https://github.com/iptv-org/iptv#playlists-by-category) (optional)