---
title: "Stream text-to-speech audio"
method: POST
path: "/voice/v1/speak/stream"
tags: ["Voice"]
---

# Stream text-to-speech audio

`POST /voice/v1/speak/stream`

Convert text to speech using ElevenLabs AI voices with streaming for real-time playback. Returns audio data as an MP3 stream for immediate playback with minimal latency. Perfect for legal document narration, client presentations, or accessibility features.

## Request body

- object
  - `text` string, required — Text to convert to speech
  - `voice_id` string — ElevenLabs voice ID (defaults to Rachel for professional clarity)
  - `model_id` 'eleven_monolingual_v1' | 'eleven_multilingual_v1' | 'eleven_multilingual_v2' | 'eleven_turbo_v2' — TTS model to use
  - `voice_settings` object — Optional voice tuning controls for delivery, consistency, and emphasis
    - `stability` number — Voice stability (0-1)
    - `similarity_boost` number — Similarity boost (0-1)
    - `style` number — Style exaggeration (0-1)
    - `use_speaker_boost` boolean — Enable speaker boost
  - `language_code` string — Language code (e.g., 'en', 'es', 'fr')
  - `output_format` 'mp3_44100_128' | 'mp3_22050_32' | 'pcm_16000' | 'pcm_22050' | 'pcm_24000' | 'pcm_44100' — Audio output format
  - `optimize_streaming_latency` integer — Optimize for streaming latency (0-4)
  - `seed` integer — Random seed for reproducible generation
  - `previous_text` string — Previous text for context
  - `next_text` string — Next text for context
  - `apply_text_normalization` boolean — Apply text normalization
  - `enable_logging` boolean — Enable request logging

## Response `200`

Audio stream successfully generated

## Other responses

- `400` — Invalid request parameters
- `401` — Authentication failed
- `403` — Insufficient permissions

---

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