Voice Settings
Fine-tune voice characteristics for your use case.
Parameters
| Parameter | Range | Default | Description |
|---|---|---|---|
stability |
0.0 - 1.0 | 0.5 | How consistent the voice sounds across the generation. Lower = more emotional variation and expressiveness (but can sound erratic). Higher = steady, predictable tone. |
similarity_boost |
0.0 - 1.0 | 0.75 | How closely to match the original voice sample. Higher sounds more like the source voice but may amplify audio artifacts or background noise from the original recording. |
style |
0.0 - 1.0 | 0.0 | Exaggerates the unique characteristics of the voice's speaking style (v2+ and v3 models only). Higher values make the voice more "characterful" but can reduce stability. |
speed |
0.25 - 4.0 | 1.0 | Speech speed multiplier. 1.0 = normal speed. Range is 0.25-4.0 for the REST API; the Agents Platform restricts to 0.7-1.2. |
use_speaker_boost |
boolean | true | Post-processing that enhances voice clarity and similarity to the original. Generally leave this on unless you're experiencing artifacts. |
Python Example
from elevenlabs import ElevenLabs
from elevenlabs import VoiceSettings
client = ElevenLabs()
audio = client.text_to_speech.convert(
text="Testing different voice settings.",
voice_id="JBFqnCBsd6RMkjVDRZzb",
model_id="eleven_v3",
voice_settings=VoiceSettings(
stability=0.5,
similarity_boost=0.75,
style=0.0,
use_speaker_boost=True
)
)JavaScript Example
const audio = await client.textToSpeech.convert("JBFqnCBsd6RMkjVDRZzb", {
text: "Testing different voice settings.",
modelId: "eleven_v3",
voiceSettings: {
stability: 0.5,
similarityBoost: 0.75,
style: 0.0,
useSpeakerBoost: true,
},
});cURL Example
curl -X POST "https://api.elevenlabs.io/v1/text-to-speech/JBFqnCBsd6RMkjVDRZzb" \
-H "xi-api-key: $ELEVENLABS_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"text": "Testing different voice settings.",
"model_id": "eleven_v3",
"voice_settings": {
"stability": 0.5,
"similarity_boost": 0.75,
"style": 0.0,
"use_speaker_boost": true
}
}' \
--output output.mp3Use Case Recommendations
Audiobooks / Narration
voice_settings=VoiceSettings(
stability=0.7, # Consistent tone
similarity_boost=0.5, # Natural variation
style=0.0
)Conversational / Chatbots
voice_settings=VoiceSettings(
stability=0.4, # More expressive
similarity_boost=0.75,
style=0.3 # Slight style emphasis
)News / Professional
voice_settings=VoiceSettings(
stability=0.8, # Very consistent
similarity_boost=0.6,
style=0.0
)Character Voices / Drama
voice_settings=VoiceSettings(
stability=0.3, # Highly expressive
similarity_boost=0.8,
style=0.5 # Strong style
)Tips
- Start with defaults and adjust incrementally
- Lower stability if voice sounds monotonous
- Reduce similarity_boost if you hear audio artifacts
- Style works with v2+, v3, and multilingual models
- Test with representative text from your actual use case
- Flash models ignore some voice settings for speed