Create speech
Generates audio from the input text.Parameters
The text to generate audio for. The maximum length is 4096 characters.
One of the available TTS models:
tts-1, tts-1-hd, gpt-4o-mini-tts, or gpt-4o-mini-tts-2025-12-15.tts-1- Standard quality, optimized for speedtts-1-hd- High definition qualitygpt-4o-mini-tts- GPT-4 optimized TTS with voice instructions supportgpt-4o-mini-tts-2025-12-15- Latest GPT-4 optimized TTS model
The voice to use when generating the audio. Supported built-in voices are
alloy, ash, ballad, coral, echo, fable, onyx, nova, sage, shimmer, verse, marin, and cedar.Previews of the voices are available in the Text to speech guide.Control the voice of your generated audio with additional instructions. Does not work with
tts-1 or tts-1-hd.The format to audio in. Supported formats are
mp3, opus, aac, flac, wav, and pcm.The speed of the generated audio. Select a value from
0.25 to 4.0. 1.0 is the default.The format to stream the audio in. Supported formats are
sse and audio. sse is not supported for tts-1 or tts-1-hd.Response
Returns the audio file content as binary data.Examples
Generate speech with different voices
Adjust speech speed
Use GPT-4 TTS with instructions
Generate in different formats
Async usage
Supported audio formats
- mp3 - MPEG audio format (default)
- opus - Opus audio format
- aac - AAC audio format
- flac - FLAC lossless audio format
- wav - Waveform audio format
- pcm - Raw PCM audio at 24kHz (16-bit signed, low-endian)
Available voices
The following voices are available for speech generation:- alloy - Neutral and balanced
- ash - Clear and articulate
- ballad - Smooth and melodic
- coral - Warm and friendly
- echo - Resonant and clear
- fable - Expressive and storytelling
- nova - Energetic and engaging
- onyx - Deep and authoritative
- sage - Calm and measured
- shimmer - Light and cheerful
- verse - Poetic and rhythmic
- marin - Natural and conversational
- cedar - Warm and grounded
Preview audio samples for each voice in the OpenAI Text-to-Speech guide.