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

# Text-to-Speech

> Convert text to natural-sounding speech with multiple voice options.

export const RuncrateStyles = () => {
  if (typeof document !== 'undefined' && !document.getElementById('runcrate-overrides')) {
    const s = document.createElement('style');
    s.id = 'runcrate-overrides';
    s.textContent = `
      /* Match Runcrate's rounding scale (--radius: 0.75rem) */
      .rounded-sm { border-radius: 0.5rem !important; }   /* 8px */
      .rounded-md { border-radius: 0.625rem !important; } /* 10px */
      .rounded-lg { border-radius: 0.75rem !important; }  /* 12px */
      .rounded-l-sm { border-top-left-radius: 0.5rem !important; border-bottom-left-radius: 0.5rem !important; }
      .rounded-r-sm { border-top-right-radius: 0.5rem !important; border-bottom-right-radius: 0.5rem !important; }
      .rounded-l-md { border-top-left-radius: 0.625rem !important; border-bottom-left-radius: 0.625rem !important; }
      .rounded-r-md { border-top-right-radius: 0.625rem !important; border-bottom-right-radius: 0.625rem !important; }
      .rounded-l-lg { border-top-left-radius: 0.75rem !important; border-bottom-left-radius: 0.75rem !important; }
      .rounded-r-lg { border-top-right-radius: 0.75rem !important; border-bottom-right-radius: 0.75rem !important; }

      /* Cards: never pure white in light mode */
      .card { background-color: #fcfcfc !important; border-radius: 0.75rem !important; }
      html.dark .card { background-color: #141414 !important; }

      /* Docs hero box */
      .rc-hero { background-color: #fcfcfc; border: 1px solid #e0e0e0; }
      html.dark .rc-hero { background-color: #141414; border-color: #242424; }
      html.dark .rc-hero h1 { color: #f5f5f5; }

      /* Runcrate scrollbar — thin, transparent track, hide-until-hover thumb */
      ::-webkit-scrollbar { width: 6px; height: 6px; background-color: transparent; }
      ::-webkit-scrollbar-track { background-color: transparent; }
      ::-webkit-scrollbar-thumb { background-color: rgba(155, 155, 155, 0.5); border-radius: 10px; transition: opacity 0.3s ease; opacity: 0; }
      ::-webkit-scrollbar-thumb:hover { background-color: rgba(155, 155, 155, 0.7); }
      *:hover::-webkit-scrollbar-thumb,
      *:focus::-webkit-scrollbar-thumb,
      *:active::-webkit-scrollbar-thumb { opacity: 1; }
      * { scrollbar-width: thin; scrollbar-color: rgba(155, 155, 155, 0.5) transparent; }
    `;
    document.head.appendChild(s);
  }
  return null;
};

<RuncrateStyles />

Generate speech audio from text input using TTS models.

## Endpoint

```
POST https://api.runcrate.ai/v1/audio/speech
```

## Basic Usage

<CodeGroup>
  ```bash curl theme={"theme":"github-dark"}
  curl https://api.runcrate.ai/v1/audio/speech \
    -H "Content-Type: application/json" \
    -H "Authorization: Bearer rc_live_YOUR_API_KEY" \
    --output speech.mp3 \
    -d '{
      "model": "hexgrad/Kokoro-82M",
      "input": "Hello, welcome to Runcrate!",
      "voice": "af_heart"
    }'
  ```

  ```python Python theme={"theme":"github-dark"}
  from openai import OpenAI

  client = OpenAI(
      base_url="https://api.runcrate.ai/v1",
      api_key="rc_live_YOUR_API_KEY",
  )

  response = client.audio.speech.create(
      model="hexgrad/Kokoro-82M",
      input="Hello, welcome to Runcrate!",
      voice="af_heart",
  )
  response.stream_to_file("speech.mp3")
  ```

  ```javascript JavaScript theme={"theme":"github-dark"}
  import OpenAI from "openai";
  import fs from "fs";

  const client = new OpenAI({
    baseURL: "https://api.runcrate.ai/v1",
    apiKey: "rc_live_YOUR_API_KEY",
  });

  const response = await client.audio.speech.create({
    model: "hexgrad/Kokoro-82M",
    input: "Hello, welcome to Runcrate!",
    voice: "af_heart",
  });
  const buffer = Buffer.from(await response.arrayBuffer());
  fs.writeFileSync("speech.mp3", buffer);
  ```
</CodeGroup>

## Parameters

| Parameter         | Type   | Description                   |
| ----------------- | ------ | ----------------------------- |
| `model`           | string | Model ID (required)           |
| `input`           | string | Text to synthesize (required) |
| `voice`           | string | Voice preset name             |
| `response_format` | string | Output format (`mp3`, `pcm`)  |

## Available Models & Voices

### Kokoro 82M

Lightweight, fast TTS with natural-sounding voices.

Voices: `af_heart`, `af_bella`, `af_nicole`, `af_sky`, `am_adam`, `am_michael`, `bf_emma`, `bf_isabella`, `bm_george`, `bm_lewis`

### Orpheus 3B

High-quality expressive speech synthesis.

Voices: `tara`, `leah`, `jess`, `leo`, `dan`, `mia`, `zac`, `zoe`

### Qwen3-TTS

Multilingual TTS from Alibaba.

Voices: `Vivian`, `Serena`, `Uncle_Fu`, `Dylan`, `Eric`, `Ryan`, `Aiden`, `Ono_Anna`, `Sohee`

### Voice-Clone Models

Some models (HiggsAudio, Zonos, Chatterbox) support voice cloning — they don't have preset voices but can clone from reference audio.

## Response

The response body is raw audio binary (MP3 or PCM). Save it directly to a file or stream it to an audio player.