Method: client.generateSpeech().
Example
const audio = await client.generateSpeech({
model: "openai/gpt-4o-mini-tts",
input: "Hello world",
voice: "alloy",
response_format: "mp3",
});
Key parameters
model (required): TTS-capable model id.
input (required): Text to synthesize.
voice: Provider-normalized voice alias (recommended) or provider-native voice value.
response_format: mp3, wav, flac, etc.
speed: Playback speed multiplier (typically 0.25-4).
If voice is not valid for the routed provider/model mapping, the API returns 400 with param: "voice".
Provider config examples
// ElevenLabs explicit override
await client.generateSpeech({
model: "eleven-labs/eleven-v3",
input: "Hello from ElevenLabs",
voice: "rachel",
config: {
elevenlabs: {
voice_id: "21m00Tcm4TlvDq8ikWAM"
}
}
});
// Google explicit override
await client.generateSpeech({
model: "google/gemini-2.5-flash-preview-tts",
input: "Hello from Gemini",
voice: "kore",
config: {
google: {
voice_name: "Kore"
}
}
});
Returns
Audio binary (Blob) Last modified on February 25, 2026