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

# Automatic language detection

> How to let Gladia detect the spoken language automatically

Gladia can automatically detect the spoken language from audio, either within a candidate set you provide or across all supported languages.

<Note>
  Provide a small list of likely languages when possible. It improves accuracy and reduces latency.
</Note>

## How to use language detection ?

You can either omit `language_config.languages` to search across all supported languages, or pass a constrained list:

<CodeGroup>
  ```json Detect across all languages theme={"system"}
  {
    "encoding": "wav/pcm",
    "sample_rate": 16000,
    "bit_depth": 16,
    "channels": 1,
    "language_config": {
      "languages": [],
      "code_switching": false
    }
  }
  ```

  ```json Detect within a set of languages theme={"system"}
  {
    "encoding": "wav/pcm",
    "sample_rate": 16000,
    "bit_depth": 16,
    "channels": 1,
    "language_config": {
      "languages": ["en", "de", "fr"],
      "code_switching": false
    }
  }
  ```
</CodeGroup>

The detected `language` is returned on each utterance and can vary over time if you also enable <a href="/chapters/language/code-switching">code switching</a>.

## Tips

* Use <a href="/chapters/language/supported-languages">supported languages</a> to pick valid ISO 639-1 codes.
* Combine with `messages_config.receive_partial_transcripts` in real time to get immediate feedback.
* For mixed-language conversations, enable <a href="/chapters/language/code-switching">code switching</a>.