Cartesia TTS | LiveKit Docs

Overview

LiveKit Inference offers voice models powered by Cartesia. Pricing information is available on the pricing page.

Model ID	Languages
cartesia/sonic	enfrdeesptzhjahiitkonlplrusvtr
cartesia/sonic-2	enfrdeesptzhjahiitkonlplrusvtr
cartesia/sonic-turbo	enfrdeesptzhjahiitkonlplrusvtr

Usage

To use Cartesia, pass a descriptor with the model and voice to the tts argument in your AgentSession:

from livekit.agents import AgentSession

session = AgentSession(
    tts="cartesia/sonic-2:9626c31c-bec5-4cca-baa8-f8ba9e84c8bc",
    # ... llm, stt, vad, turn_detection, etc.
)

import { AgentSession } from '@livekit/agents';

session = new AgentSession({
    tts="cartesia/sonic-2:9626c31c-bec5-4cca-baa8-f8ba9e84c8bc",
    // ... tts, stt, vad, turn_detection, etc.
});

Parameters

To customize additional parameters, use the TTS class from the inference module:

from livekit.agents import AgentSession, inference

session = AgentSession(
    tts=inference.TTS(
        model="cartesia/sonic-2", 
        voice="9626c31c-bec5-4cca-baa8-f8ba9e84c8bc", 
        language="en"
    ),
    # ... tts, stt, vad, turn_detection, etc.
)

import { AgentSession } from '@livekit/agents';

session = new AgentSession({
    tts: new inference.TTS({ 
        model: "cartesia/sonic-2", 
        voice: "9626c31c-bec5-4cca-baa8-f8ba9e84c8bc", 
        language: "en" 
    }),
    // ... tts, stt, vad, turn_detection, etc.
});

modelstringRequired

The model ID from the models list.

voicestringRequired

See voices for guidance on selecting a voice.

languagestringOptional

Language code for the input text. If not set, the model default applies.

extra_kwargsdictOptional

Additional parameters to pass to the Cartesia TTS API, including duration, and speed. See the provider's documentation for more information.

Voices

LiveKit Inference supports all of the default "Cartesia Voices" available in the Cartesia API. You can explore the available voices in the Cartesia voice library (free account required), and use the voice by copying its ID into your LiveKit agent session.

Custom voices unavailable

Custom Cartesia voices, including voice cloning, are not yet supported in LiveKit Inference. To use custom voices, create your own Cartesia account and use the Cartesia plugin for LiveKit Agents instead.

The following is a small sample of the Cartesia voices available in LiveKit Inference.

Use the keyboard and arrows to audition voices

Additional resources

The following links provide more information about Cartesia in LiveKit Inference.

Cartesia Plugin

Plugin to use your own Cartesia account instead of LiveKit Inference.

Cartesia docs

Cartesia's official API documentation.