Source: https://01router.com/docs/models/elevenlabs-tts-v4-turbo/create
Base URL: https://01router.com/api/v1

# ElevenLabs Eleven v4 Turbo · Create a generation

Pass the model id, its unified input parameters and optionally a provider slug. The response returns immediately with the task id; image models on synchronous providers may already be succeeded.

`POST /api/v1/generations`

Bearer API key

## Input parameters

| Field | Type | Required | Description | Constraints |
| --- | --- | --- | --- | --- |
| model | string | yes | Model slug from the catalog. Project keys may use a project-specific model slug. | options: [   "elevenlabs-tts-v4-turbo" ] |
| input | object | yes | Model-specific input object. See the selected model reference for required fields, defaults and limits. |  |
| provider | string | no | Optional provider slug. Omit for automatic routing; project settings may pin the provider. |  |
| project | string | no | Optional project ID. Use its published model catalog and routing configuration. |  |
| callback_url | string<uri> | no | Public HTTPS URL, up to 1,000 characters. Receives the final generation object. Private network addresses are rejected. |  |
| input.prompt | string | yes |  | maxLength: 5000 |
| input.voice | string | no |  | default: "Rachel" |
| input.stability | number | no |  | default: 0.5; min: 0; max: 1 |
| input.similarity_boost | number | no |  | default: 0.75; min: 0; max: 1 |
| input.language_code | string | no | ISO 639-1, e.g. en or zh |  |
| input.seed | integer | no |  | min: 0; max: 4294967295 |
| input.output_format | enum | no |  | default: "mp3_44100_128"; options: [   "mp3_22050_32",   "mp3_44100_32",   "mp3_44100_64",   "mp3_44100_96",   "mp3_44100_128",   "mp3_44100_192",   "pcm_8000",   "pcm_16000",   "pcm_22050",   "pcm_24000",   "pcm_44100",   "pcm_48000",   "ulaw_8000",   "alaw_8000",   "opus_48000_32",   "opus_48000_64",   "opus_48000_96",   "opus_48000_128",   "opus_48000_192" ] |
| input.apply_text_normalization | enum | no |  | default: "auto"; options: [   "auto",   "on",   "off" ] |

## Response fields

| Field | Type | Required | Description | Constraints |
| --- | --- | --- | --- | --- |
| id | string | — | Generation ID returned by the create request. |  |
| object | "generation" | — | generation |  |
| model | string | — | Model slug from the catalog. Project keys may use a project-specific model slug. |  |
| type | video \| image \| audio \| chat | — |  |  |
| provider | string | — | Optional provider slug. Omit for automatic routing; project settings may pin the provider. |  |
| status | string | — | queued / processing / succeeded / failed. Stop polling on succeeded or failed. |  |
| input | object | — | Model-specific input object. See the selected model reference for required fields, defaults and limits. |  |
| outputs | string[] | — | Result file URLs. Empty until available; download promptly because URLs may expire. |  |
| error | string \| null | — | Error message on failure; null otherwise. |  |
| credits | number | — | Credits charged for this generation; zero after a refund. |  |
| price_usd | number | — | Price of this generation in USD; zero after a refund. |  |
| created_at | string | — | Creation time in ISO 8601 format. |  |
| completed_at | string \| null | — | Completion time in ISO 8601 format, or null while running. |  |

## cURL

```bash
curl 'https://01router.com/api/v1/generations' \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "elevenlabs-tts-v4-turbo",
  "input": {
    "prompt": "A cinematic landscape at sunrise.",
    "voice": "Rachel",
    "stability": 0.5,
    "similarity_boost": 0.75,
    "output_format": "mp3_44100_128",
    "apply_text_normalization": "auto"
  }
}'
```

## 200 · application/json

```json
{
  "id": "gen_example",
  "object": "generation",
  "model": "elevenlabs-tts-v4-turbo",
  "type": "audio",
  "provider": "fal",
  "status": "processing",
  "input": {
    "prompt": "A cinematic landscape at sunrise.",
    "voice": "Rachel",
    "stability": 0.5,
    "similarity_boost": 0.75,
    "output_format": "mp3_44100_128",
    "apply_text_normalization": "auto"
  },
  "outputs": [],
  "error": null,
  "credits": 100,
  "price_usd": 1,
  "created_at": "2026-10-25T08:00:00.000Z",
  "completed_at": null
}
```

## Usage notes

- Poll at intervals of at least 3 seconds. A 504 from the synchronous image endpoint means the task may still be running: poll its error.id instead of submitting it again.