The following language strings are recognized by setlocale. Any language not supported by the operating system is not accepted by setlocale. The three-letter language-string codes are only valid in Windows 2000 and later operating systems.
| Primary language | Sublanguage | Language string | 
|---|---|---|
| Chinese | Chinese | "chinese" | 
| Chinese | Chinese (simplified) | "chinese-simplified" or "chs" | 
| Chinese | Chinese (traditional) | "chinese-traditional" or "cht" | 
| Czech | Czech | "csy" or "czech" | 
| Danish | Danish | "dan" or "danish" | 
| Dutch | Dutch (default) | "dutch" or "nld" | 
| Dutch | Dutch (Belgium) | "belgian", "dutch-belgian", or "nlb" | 
| English | English (default) | "english" | 
| English | English (Australia) | "australian", "ena", or "english-aus" | 
| English | English (Canada) | "canadian", "enc", or "english-can" | 
| English | English (New Zealand) | "english-nz" or "enz" | 
| English | English (United Kingdom) | "eng", "english-uk", or "uk" | 
| English | English (United States) | "american", "american english", "american-english", "english-american", "english-us", "english-usa", "enu", "us", or "usa" | 
| Finnish | Finnish | "fin" or "finnish" | 
| French | French (default) | "fra" or "french" | 
| French | French (Belgium) | "frb" or "french-belgian" | 
| French | French (Canada) | "frc" or "french-canadian" | 
| French | French (Switzerland) | "french-swiss" or "frs" | 
| German | German (default) | "deu" or "german" | 
| German | German (Austria) | "dea" or "german-austrian" | 
| German | German (Switzerland) | "des", "german-swiss", or "swiss" | 
| Greek | Greek | "ell" or "greek" | 
| Hungarian | Hungarian | "hun" or "hungarian" | 
| Icelandic | Icelandic | "icelandic" or "isl" | 
| Italian | Italian (default) | "ita" or "italian" | 
| Italian | Italian (Switzerland) | "italian-swiss" or "its" | 
| Japanese | Japanese | "japanese" or "jpn" | 
| Korean | Korean | "kor" or "korean" | 
| Norwegian | Norwegian (default) | "norwegian" | 
| Norwegian | Norwegian (Bokmal) | "nor" or "norwegian-bokmal" | 
| Norwegian | Norwegian (Nynorsk) | "non" or "norwegian-nynorsk" | 
| Polish | Polish | "plk" or "polish" | 
| Portuguese | Portuguese (default) | "portuguese" or "ptg" | 
| Portuguese | Portuguese (Brazil) | "portuguese-brazilian" or "ptb" | 
| Russian | Russian (default) | "rus" or "russian" | 
| Slovak | Slovak | "sky" or "slovak" | 
| Spanish | Spanish (default) | "esp" or "spanish" | 
| Spanish | Spanish (Mexico) | "esm" or "spanish-mexican" | 
| Spanish | Spanish (Modern) | "esn" or "spanish-modern" | 
| Swedish | Swedish | "sve" or "swedish" | 
| Turkish | Turkish | "trk" or "turkish" |