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Audio
Speech

Create speech

audio.speech.create(**kwargs) -> StringIO
POST/audio/speech

Generates audio from the input text.

Returns the audio file content, or a stream of audio events.

ParametersExpand Collapse
input: String

The text to generate audio for. The maximum length is 4096 characters.

maxLength4096
model: String | SpeechModel

One of the available TTS models: tts-1, tts-1-hd, gpt-4o-mini-tts, or gpt-4o-mini-tts-2025-12-15.

One of the following:
String
SpeechModel = :"tts-1" | :"tts-1-hd" | :"gpt-4o-mini-tts" | :"gpt-4o-mini-tts-2025-12-15"
One of the following:
:"tts-1"
:"tts-1-hd"
:"gpt-4o-mini-tts"
:"gpt-4o-mini-tts-2025-12-15"
voice: String | :alloy | :ash | :ballad | 7 more | { id}

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. You may also provide a custom voice object with an id, for example { "id": "voice_1234" }. Previews of the voices are available in the Text to speech guide.

One of the following:
String
:alloy | :ash | :ballad | 7 more
One of the following:
:alloy
:ash
:ballad
:coral
:echo
:sage
:shimmer
:verse
:marin
:cedar
class ID { id }

Custom voice reference.

id: String

The custom voice ID, e.g. voice_1234.

instructions: String

Control the voice of your generated audio with additional instructions. Does not work with tts-1 or tts-1-hd.

maxLength4096
response_format: :mp3 | :opus | :aac | 3 more

The format to audio in. Supported formats are mp3, opus, aac, flac, wav, and pcm.

One of the following:
:mp3
:opus
:aac
:flac
:wav
:pcm
speed: Float

The speed of the generated audio. Select a value from 0.25 to 4.0. 1.0 is the default.

minimum0.25
maximum4
stream_format: :sse | :audio

The format to stream the audio in. Supported formats are sse and audio. sse is not supported for tts-1 or tts-1-hd.

One of the following:
:sse
:audio
ReturnsExpand Collapse
StringIO

Create speech

require "openai"

openai = OpenAI::Client.new(api_key: "My API Key")

speech = openai.audio.speech.create(input: "input", model: :"tts-1", voice: "string")

puts(speech)
Returns Examples