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

# Speech-to-text, diarization and speaker ID API

> Speech-to-text, speaker diarization and speaker identification: live streaming, batch transcription, who spoke when, and who is speaking.

The AirCaps AI API has four models:

| Model | ID | Use it for |
| - | - | - |
| **A5S Async v1** | `a5s-async-v1` | Recorded audio: transcripts with speaker labels, word timestamps, subtitles |
| **A5S Small V2 Streaming** | `a5s-small-v2-streaming` | Live audio: captions as people speak |
| **AirCaps Diarization-v1** | `aircaps-diarization-v1` | Recorded audio: who spoke when, without a transcript |
| **AirCaps Speaker ID-v1** | `aircaps-speaker-id-v1` | Enrolled voices: which known person is speaking |

Base URL: `https://api.aircaps.com/v1`

**Every account includes 5 hours of free usage**, shared by all models. After that, usage is pay as you go: add credits in the console, where the prices are listed. AirCaps Diarization-v1 and AirCaps Speaker ID-v1 are enabled per account on request. For volume pricing, higher limits or concurrency, model access, or a dedicated deployment, [talk to sales](https://aircaps.ai/contact).

We don't train on your data; see [Data & privacy](https://aircaps.ai/docs/data-privacy.md).

A5S Async v1 and A5S Small V2 Streaming transcribe **English** today. Multilingual support is planned and will be available soon. AirCaps Diarization-v1 and AirCaps Speaker ID-v1 work from the voice, not the words.

> [card] [Quickstart](https://aircaps.ai/docs/quickstart.md)
>
> A first request to each model.

> [card] [API keys](https://aircaps.ai/docs/authentication.md)
>
> Create and use a key.

> [card] [Batch transcription](https://aircaps.ai/docs/guides/async-transcription.md)
>
> Uploads, URLs, polling and webhooks.

> [card] [Live streaming](https://aircaps.ai/docs/guides/streaming.md)
>
> The realtime WebSocket protocol.

> [card] [Speaker diarization](https://aircaps.ai/docs/guides/diarization.md)
>
> Who spoke when in a recording.

> [card] [Speaker identification](https://aircaps.ai/docs/guides/speaker-id.md)
>
> Enroll voices, then recognize them.

> [card] [Talk to sales](https://aircaps.ai/contact)
>
> Pricing, higher limits and concurrency, model access, and dedicated deployments.

> [!TIP]
>
> Try every model without code in the [Playground](https://playground.aircaps.com/playground).


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