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

# Choosing a speech-to-text provider

> How to pick the right speech-to-text provider for your Bolna agent based on language, latency and accuracy.

The transcriber turns the caller's audio into text. Language support is the primary selection factor — most transcribers are optimized for specific language families.

| Provider | Best for | Notes |
| - | - | - |
| **Deepgram Nova-3** | English | Fastest; best accuracy for English |
| **Deepgram Nova-2** | Many languages | Broader language coverage |
| **ElevenLabs** | English | High accuracy; slightly higher latency |
| **Azure Speech** | Enterprise, many languages | Strong multilingual; good for EU |
| **AssemblyAI** | English | High accuracy; async features |
| **Sarvam** | Indian languages | Best for Hindi, Tamil, Bengali, Telugu, Marathi, etc. |
| **Gladia** | European languages | Good multilingual coverage |
| **Soniox** | Code-switching | One model auto-detects and switches language mid-sentence |
| **Smallest AI** | Ultra-low latency | Pulse model; sub-100ms first-token latency |
| **Gemini 3.5 Transcribe** | Multilingual | High accuracy and low latency across many languages |
| **Deepgram Flux** | Lowest latency | Turn detection inside the model; enables speculative LLM responses and instant barge-in |
| **OpenAI Realtime** | Clean or accented audio | Built-in VAD; `delay` trades latency against accuracy |
| **Google** | Broad language coverage | Google Cloud Speech-to-Text |

Key settings: `endpointing` (silence detection), `language` (always set explicitly — auto-detection adds latency), `encoding` / `sampling_rate` (must match your telephony provider). For the exact `provider` and `model` values each takes, see [Create Agent](/docs/api-reference/agent/v2/create#transcriber).

***

## Next steps

<CardGroup cols={2}>
  <Card title="Speech-to-text providers" icon="microphone" href="/docs/speech-to-text">
    Setup guides for every transcriber Bolna supports
  </Card>

  <Card title="Supported languages" icon="language" href="/docs/customizations/supported-languages">
    Languages and codes you can configure
  </Card>

  <Card title="Choose an LLM" icon="brain" href="/docs/concepts/choosing-llm">
    The next provider in the pipeline
  </Card>

  <Card title="Back to the decision guide" icon="sliders" href="/docs/concepts/choosing-providers">
    Compare all provider categories side by side
  </Card>
</CardGroup>


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