> ## Documentation Index
> Fetch the complete documentation index at: https://heygen-1fa696a7.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# HeyGen Voice

> HeyGen Voice is HeyGen's in-house voice model, powering professional voice clones and direct completed or streaming speech synthesis.

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<Warning>
  The HeyGen Voice APIs are in private preview. Your account must be enabled before these endpoints are available — see [how to request access](/docs/voices/professional-voice-clone#get-private-preview-access).
</Warning>

HeyGen Voice is HeyGen's in-house voice model. It trains a dedicated voice adapter per speaker and synthesizes speech directly from that adapter, giving the highest-fidelity voice output HeyGen offers.

## What it does

* **Professional voice cloning** — train a dedicated voice from 1–10 recordings of the same speaker totaling at least 20 minutes. Training runs asynchronously; poll until the voice is `ACTIVE`. See [HeyGen Professional Clone](/docs/voices/professional-voice-clone). For cloning from a single short recording, see [HeyGen Instant Clone](/docs/voices/instant-voice-clone) on the Starfish engine.
* **Speech generation** — synthesize speech from an `ACTIVE` voice as one completed 44.1 kHz WAV, or stream ordered audio parts over Server-Sent Events with optional word-level timestamps. See [HeyGen Voice Speech](/docs/voices/heygen-voice-speech).

## Endpoints

| Endpoint                                    | Purpose                                   |
| ------------------------------------------- | ----------------------------------------- |
| `POST /v3/models/audio/voices`              | Create or retrain a professional voice.   |
| `GET /v3/models/audio/voices/{voice_id}`    | Read a voice and its training status.     |
| `GET /v3/models/audio/voices`               | List your HeyGen Voice audio voices.      |
| `DELETE /v3/models/audio/voices/{voice_id}` | Delete a voice.                           |
| `POST /v3/models/audio/tts`                 | Generate one completed audio file.        |
| `POST /v3/models/audio/tts/stream`          | Stream audio parts as they are generated. |

## HeyGen Voice and third-party voices

The [voices catalog](/docs/voices/overview) (`/v3/voices`) covers HeyGen's 300+ stock voices, [designed voices](/docs/voices/design-voices), and [HeyGen instant clones](/docs/voices/instant-voice-clone) on the Starfish engine, synthesized through [Third Party Speech](/docs/voices/speech). HeyGen Voice is HeyGen's own model surface: its professional voices are created and used through the `/v3/models/audio` endpoints, scoped to the workspace that trained them.