# Cartesia Sonic 3

Cartesia Sonic 3 turns text into speech for $0.065 per 1K characters on LLM API.

Model ID: `sonic-3` · Cartesia · Text to speech · Released October 31, 2025
Updated: 2026-10-13
Canonical: https://llmapi.ai/models/sonic-3/

- Per 1K characters: $0.065
- Task: Text to speech

## Pricing

Served by Cartesia, the only provider.

| Price | Amount | Per |
| --- | --- | --- |
| Text to speech | $0.065 | per 1K characters |

**Volume pricing.** At higher monthly volume, Cartesia Sonic 3 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).

## Call Cartesia Sonic 3

### 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",
    voice="f786b574-daa5-4673-aa0c-cbe3e8534c02",
    input="Hello from LLM API",
)
speech.write_to_file("hello.mp3")
```

Docs: [Speech docs](https://docs.llmapi.ai/api/v1/audio)

## More from Cartesia

- [Cartesia Sonic 3.5](https://llmapi.ai/models/sonic-3-5/): $0.078 per 1K characters
- [Cartesia Sonic 3 (2026-01-12)](https://llmapi.ai/models/sonic-3-2026-01-12/): $0.065 per 1K characters
- [Cartesia Ink Whisper](https://llmapi.ai/models/openai-ink-whisper/): $0.0022 per minute

Prices synced 2026-11-09.

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