# Cartesia

Cartesia serves 7 audio models on LLM API, all from Cartesia.

7 models
Updated: 2026-10-13
Canonical: https://llmapi.ai/providers/cartesia/

## Models and prices

Prices when Cartesia serves the request.

### Audio (7)

Price per minute of audio or per 1K characters.

| Model | Model ID | Task | Price |
| --- | --- | --- | --- |
| [Cartesia Sonic 3.5](https://llmapi.ai/models/sonic-3-5/) | `sonic-3.5` | Text to speech | $0.078 / 1K characters |
| [Cartesia Sonic 3 (2026-01-12)](https://llmapi.ai/models/sonic-3-2026-01-12/) | `sonic-3-2026-01-12` | Text to speech | $0.065 / 1K characters |
| [Cartesia Sonic 3](https://llmapi.ai/models/sonic-3/) | `sonic-3` | Text to speech | $0.065 / 1K characters |
| [Cartesia Ink Whisper](https://llmapi.ai/models/openai-ink-whisper/) | `ink-whisper` | Transcription | $0.0022 / minute |
| [Cartesia Ink 2 (Streaming)](https://llmapi.ai/models/ink-2/) | `ink-2` | Live transcription | $0.013 / minute |
| [Cartesia Sonic Turbo](https://llmapi.ai/models/sonic-turbo/) | `sonic-turbo` | Text to speech | $0.045 / 1K characters |
| [Cartesia Sonic 2](https://llmapi.ai/models/sonic-2/) | `sonic-2` | Text to speech | $0.065 / 1K characters |

**Volume pricing.** At higher monthly volume, models on Cartesia may cost less. Book a call and sales will quote a price for your usage. [Book a call with sales](https://meetings.hubspot.com/julia-andriienko/llmapi) or [Create an account first](https://app.llmapi.ai/signup).

## Send requests to Cartesia

Use the model ID as it is: video, audio and embedding requests take no provider prefix.

Example: Cartesia Sonic 3.5, Speech (`POST /v1/audio/speech`). Set LLMAPI_KEY to your LLM API key.

```python
import os

from openai import OpenAI

client = OpenAI(
    base_url="https://api.llmapi.ai/v1",
    api_key=os.environ["LLMAPI_KEY"],
)

speech = client.audio.speech.create(
    model="sonic-3.5",
    voice="f786b574-daa5-4673-aa0c-cbe3e8534c02",
    input="Hello from LLM API",
)
speech.write_to_file("hello.mp3")
```

Prices synced 2026-10-27.

Next step: [Get API key](https://app.llmapi.ai/signup)