These are all the language codes you can retrieve from people’s browsers (in php with $_SERVER['HTTP_ACCEPT_LANGUAGE'] for instance)
| af | Afrikaans |
| sq | Albanian |
| ar-sa | Arabic(Saudi Arabia) |
| ar-iq | Arabic(Iraq) |
| ar-eg | Arabic(Egypt) |
| ar-ly | Arabic(Libya) |
| ar-dz | Arabic(Algeria) |
| ar-ma | Arabic(Morocco) |
| ar-tn | Arabic(Tunisia) |
| ar-om | Arabic(Oman) |
| ar-ye | Arabic(Yemen) |
| ar-sy | Arabic(Syria) |
| ar-jo | Arabic(Jordan) |
| ar-lb | Arabic(Lebanon) |
| ar-kw | Arabic(Kuwait) |
| ar-ae | Arabic(U.A.E.) |
| ar-bh | Arabic(Bahrain) |
| ar-qa | Arabic(Qatar) |
| eu | Basque |
| bg | Bulgarian |
| be | Belarusian |
| ca | Catalan |
| zh-tw | Chinese(Taiwan) |
| zh-cn | Chinese(PRC) |
| zh-hk | Chinese(Hong Kong) |
| zh-sg | Chinese(Singapore) |
| hr | Croatian |
| cs | Czech |
| da | Danish |
| nl | Dutch(Standard) |
| nl-be | Dutch(Belgian) |
| en | English |
| en-us | English(United States) |
| en-gb | English(British) |
| en-au | English(Australian) |
| en-ca | English(Canadian) |
| en-nz | English(New Zealand) |
| en-ie | English(Ireland) |
| en-za | English(South Africa) |
| en-jm | English(Jamaica) |
| en-ca | English(Caribbean) |
| en-bz | English(Belize) |
| en-tt | English(Trinidad) |
| et | Estonian |
| fo | Faeroese |
| fa | Farsi |
| fi | Finnish |
| fr | French(Standard) |
| fr-be | French(Belgian) |
| fr-ca | French(Canadian) |
| fr-ch | French(Swiss) |
| fr-lu | French(Luxembourg) |
| mk | Macedonian (FYROM) |
| gd | Gaelic(Scots) |
| de | German(Standard) |
| de-ch | German(Swiss) |
| de-at | German(Austrian) |
| de-lu | German(Luxembourg) |
| de-li | German(Liechtenstein) |
| el | Greek |
| he | Hebrew |
| hi | Hindi |
| hu | Hungarian |
| is | Icelandic |
| in | Indonesian |
| it | Italian(Standard) |
| it-ch | Italian(Swiss) |
| ja | Japanese |
| ko | Korean |
| ko | Korean(Johab) |
| lv | Latvian |
| lt | Lithuanian |
| ms | Malaysian |
| mt | Maltese |
| no | Norwegian(Bokmal) |
| no | Norwegian(Nynorsk) |
| pl | Polish |
| pt-br | Portuguese(Brazil) |
| pt | Portuguese(Portugal) |
| rm | Rhaeto-Romanic |
| ro | Romanian |
| ro-mo | Romanian(Moldavia) |
| ru | Russian |
| ru-mo | Russian(Moldavia) |
| sz | Sami(Lappish) |
| sr | Serbian(Cyrillic) |
| sr | Serbian(Latin) |
| sk | Slovak |
| sl | Slovenian |
| sb | Sorbian |
| es | Spanish(Spain – Traditional Sort) |
| es-mx | Spanish(Mexican) |
| es-gt | Spanish(Guatemala) |
| es-cr | Spanish(Costa Rica) |
| es-pa | Spanish(Panama) |
| es-do | Spanish(Dominican Republic) |
| es-ve | Spanish(Venezuela) |
| es-co | Spanish(Colombia) |
| es-pe | Spanish(Peru) |
| es-ar | Spanish(Argentina) |
| es-ec | Spanish(Ecuador) |
| es-c | Spanish(Chile) |
| es-uy | Spanish(Uruguay) |
| es-py | Spanish(Paraguay) |
| es-bo | Spanish(Bolivia) |
| es-sv | Spanish(El Salvador) |
| es-hn | Spanish(Honduras) |
| es-ni | Spanish(Nicaragua) |
| es-pr | Spanish(Puerto Rico) |
| sx | Sutu |
| sv | Swedish |
| sv-fi | Swedish(Finland) |
| th | Thai |
| ts | Tsonga |
| tn | Tswana |
| tr | Turkish |
| uk | Ukrainian |
| ur | Urdu |
| ve | Venda |
| vi | Vietnamese |
| xh | Xhosa |
| ji | Yiddish |
| zu | Zulu |