This is a list of languages that SharePoint Online supports and the codes to represent them:

Name Language Tag LCID
Arabic ar-SA 1025
Azerbaijani az-Latn-AZ 1068
Basque eu-ES 1069
Bosnian (Latin) bs-Latn-BA 5146
Bulgarian bg-BG 1026
Catalan ca-ES 1027
Chinese (Simplified) zh-CN 2052
Chinese (Traditional) zh-TW 1028
Croatian hr-HR 1050
Czech cs-CZ 1029
Danish da-DK 1030
Dari prs-AF 1164
Dutch nl-NL 1043
English en-US 1033
Estonian et-EE 1061
Finnish fi-FI 1035
French fr-FR 1036
Galician gl-ES 1110
German de-DE 1031
Greek el-GR 1032
Hebrew he-IL 1037
Hindi hi-IN 1081
Hungarian hu-HU 1038
Indonesian id-ID 1057
Irish ga-IE 2108
Italian it-IT 1040
Japanese ja-JP 1041
Kazakh kk-KZ 1087
Korean ko-KR 1042
Latvian lv-LV 1062
Lithuanian lt-LT 1063
Macedonian mk-MK 1071
Malay ms-MY 1086
Norwegian (Bokmål) nb-NO 1044
Polish pl-PL 1045
Portuguese (Brazil) pt-BR 1046
Portuguese (Portugal) pt-PT 2070
Romanian ro-RO 1048
Russian ru-RU 1049
Serbian (Cyrillic, Serbia) sr-Cyrl-RS 10266
Serbian (Latin) sr-Latn-CS 2074
Serbian (Latin, Serbia) sr-Latn-RS 9242
Slovak sk-SK 1051
Slovenian sl-SI 1060
Spanish es-ES 3082
Swedish sv-SE 1053
Thai th-TH 1054
Turkish tr-TR 1055
Ukrainian uk-UA 1058
Vietnamese vi-VN 1066
Welsh cy-GB 1106