> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sully.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Supported Languages

Our Audio Transcription API accepts [BCP47 language tags](https://en.wikipedia.org/wiki/IETF_language_tag). This page lists every tag the API accepts today (**89** locale codes, plus `multi` for multilingual transcription).

## Languages

| Language                         | Language Tags                                                                                                      |
| -------------------------------- | ------------------------------------------------------------------------------------------------------------------ |
| Arabic                           | ar, ar-AE, ar-SA, ar-QA, ar-KW, ar-SY, ar-LB, ar-PS, ar-JO, ar-EG, ar-SD, ar-TD, ar-MA, ar-DZ, ar-TN, ar-IQ, ar-IR |
| Belarusian                       | be                                                                                                                 |
| Bengali                          | bn                                                                                                                 |
| Bosnian                          | bs                                                                                                                 |
| Bulgarian                        | bg                                                                                                                 |
| Catalan                          | ca                                                                                                                 |
| Chinese (Mandarin, Simplified)   | zh, zh-CN, zh-Hans                                                                                                 |
| Chinese (Mandarin, Traditional)  | zh-TW, zh-Hant                                                                                                     |
| Chinese (Cantonese, Traditional) | zh-HK                                                                                                              |
| Croatian                         | hr                                                                                                                 |
| Czech                            | cs                                                                                                                 |
| Danish                           | da, da-DK                                                                                                          |
| Dutch                            | nl                                                                                                                 |
| English                          | en, en-US, en-CA, en-IE, en-AU, en-GB, en-NZ, en-IN                                                                |
| Estonian                         | et                                                                                                                 |
| Finnish                          | fi                                                                                                                 |
| Flemish                          | nl-BE                                                                                                              |
| French                           | fr, fr-CA                                                                                                          |
| German                           | de, de-CH                                                                                                          |
| Greek                            | el                                                                                                                 |
| Gujarati                         | gu, gu-IN                                                                                                          |
| Hebrew                           | he                                                                                                                 |
| Hindi                            | hi                                                                                                                 |
| Hungarian                        | hu                                                                                                                 |
| Indonesian                       | id                                                                                                                 |
| Italian                          | it                                                                                                                 |
| Japanese                         | ja                                                                                                                 |
| Kannada                          | kn                                                                                                                 |
| Korean                           | ko, ko-KR                                                                                                          |
| Latvian                          | lv                                                                                                                 |
| Lithuanian                       | lt                                                                                                                 |
| Macedonian                       | mk                                                                                                                 |
| Malay                            | ms                                                                                                                 |
| Marathi                          | mr                                                                                                                 |
| Norwegian                        | no                                                                                                                 |
| Persian                          | fa                                                                                                                 |
| Polish                           | pl                                                                                                                 |
| Portuguese                       | pt, pt-BR, pt-PT                                                                                                   |
| Romanian                         | ro                                                                                                                 |
| Russian                          | ru                                                                                                                 |
| Serbian                          | sr                                                                                                                 |
| Slovak                           | sk                                                                                                                 |
| Slovenian                        | sl                                                                                                                 |
| Spanish                          | es, es-419                                                                                                         |
| Swedish                          | sv, sv-SE                                                                                                          |
| Tagalog                          | tl                                                                                                                 |
| Tamil                            | ta                                                                                                                 |
| Telugu                           | te                                                                                                                 |
| Thai                             | th, th-TH                                                                                                          |
| Turkish                          | tr                                                                                                                 |
| Ukrainian                        | uk                                                                                                                 |
| Urdu                             | ur                                                                                                                 |
| Vietnamese                       | vi                                                                                                                 |

<Note>
  Tags not listed here are rejected with a validation error on upload and streaming endpoints. Use exact casing (for example `en-US`, not `en-us`).
</Note>

## Multilingual Support

Multilingual transcription detects and transcribes multiple languages in the same audio. Use it when speakers switch languages during the encounter.

### Automatic multilingual routing

If you pass any of the following base language tags, the API routes the request through multilingual code-switching (the same upstream behavior as `language=multi`):

| Language   | Language Tags |
| ---------- | ------------- |
| Dutch      | nl            |
| French     | fr            |
| German     | de            |
| Hindi      | hi            |
| Italian    | it            |
| Japanese   | ja            |
| Portuguese | pt            |
| Russian    | ru            |
| Spanish    | es            |

For example, `language=es` and `language=multi` both use multilingual code-switching. To target a single Spanish locale without that routing, use a regional tag such as `es-419`.

### Explicit `multi` tag

You may also pass `multi` directly:

```
wss://api.sully.ai/v1/audio/transcriptions/stream?language=multi&sample_rate=16000
```

`multi` is accepted on streaming endpoints. File upload accepts the locale codes in the table above; use `multi` on streaming when you want the same multilingual behavior without picking a base language first.