Guides
Build with Sonic
The quickest way to get started with Sonic is by using an integration.
If you are using the API directly, check out Cartesia’s client libraries and AI tools.
The references section contains complete documentation for all API endpoints and best practices.
Build a voice agent
Skills for coding agents
The official Cartesia SDKs
Simple scripts using Sonic
Prompting tips
Get natural-sounding output from Sonic with minimal prompt engineering.
Custom Pronunciations
Specify custom pronunciations for words that are hard to get right, like proper nouns or domain-specific terms.
Volume, Speed, and Emotion
Control the speed, volume, and emotion of generated speech.
SSML Tags
Laughter, pauses, and mid-transcript controls
Compare TTS Endpoints
How bytes, SSE, and WebSocket differ for text-to-speech, and when to use each.
Output Format
How to find the right parameters for output audio
Migrating from Sonic 3 to Sonic 3.5
What's new in Sonic 3.5 and what to know before you switch.