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

# Migrate from ElevenLabs

> Replace ElevenLabs TTS calls with Gradium REST and WebSocket endpoints.

If your app already sends text to a provider and writes the returned
audio to a file or stream, the migration is intentionally small: change
the endpoint to Gradium, send your Gradium API key as `x-api-key`, and
use a Gradium `voice_id`. The playback path can usually stay the same.

## Endpoint swap

| Flow          | Existing integration                                                | Gradium                                           |
| ------------- | ------------------------------------------------------------------- | ------------------------------------------------- |
| One-shot TTS  | `POST https://api.elevenlabs.io/v1/text-to-speech/{voice_id}`       | `POST https://api.gradium.ai/api/post/speech/tts` |
| Streaming TTS | `wss://api.elevenlabs.io/v1/text-to-speech/{voice_id}/stream-input` | `wss://api.gradium.ai/api/speech/tts`             |

## Request mapping

For POST requests, the most important change is that Gradium takes the
voice in the JSON body instead of the URL path:

| Existing concept                  | Gradium field      |
| --------------------------------- | ------------------ |
| `{voice_id}` path parameter       | `voice_id`         |
| `text`                            | `text`             |
| `model_id`                        | `model_name`       |
| Output format query/body settings | `output_format`    |
| Provider API-key header           | `x-api-key` header |

Use the [Gradium POST example](/guides/migration#gradium-post-example)
as the replacement request. It returns raw audio bytes when
`only_audio` is `true`, so existing "save the response body as audio"
code can stay the same.

## WebSocket mapping

For streaming TTS, the Gradium lifecycle is:

1. Connect to `wss://api.gradium.ai/api/speech/tts`.
2. Send a `setup` message with `voice_id`, `model_name`, and `output_format`.
3. Send one or more `text` messages.
4. Send `end_of_stream`.
5. Read `audio` messages until Gradium sends `end_of_stream`.

Use the [Gradium WebSocket example](/guides/migration#gradium-websocket-example)
as the minimal replacement. Your receive loop should continue buffering
audio chunks in the same place it buffered provider audio.

## Checklist

* Replace the provider URL with the Gradium endpoint.
* Change auth to `x-api-key`.
* Move the voice id from the URL path into `voice_id`.
* Use a Gradium voice id from the [voice library](/guides/voices/flagship-voices).
* Keep your existing audio write/playback path.

<Card title="Gradium TTS REST guide" icon="file-lines" href="/guides/text-to-speech-rest">
  Full POST schema, response modes, and supported output formats.
</Card>