Connect your Cartesia Sonic-3 API Key to generate unlimited, ultra-low latency speech and synthesize custom cloned voices directly from your browser.
Learn how to connect your developer credentials, configure high-fidelity clones, and maximize character quotas.
Cartesia Sonic-3 is engineered for ultra-fast, state-of-the-art neural speech synthesis. With sub-100ms time-to-first-audio latency and rich emotional intonation, it provides studio-grade quality for podcasts, voiceovers, and conversational AI.
Upload a clean 10-20 second audio sample in the Cartesia console under "Instant Clone". The model extracts speaker identity vectors without fine-tuning, generating an exact cloned Voice ID that works immediately in this studio.
Yes, absolutely. Your API key is stored strictly inside your browser's localStorage and is never transmitted to or logged by our servers. All API requests communicate directly with Cartesia AI.
Click the "Open Visual Guide" tutorial banner at the top of this page. It walks you through signing up for Cartesia, cloning your first voice, and generating your developer API key in 19 step-by-step screenshots.
Cartesia provides 20,000 characters free on their developer starter plan. When your quota is exhausted, you can easily upgrade on Cartesia's console to unlock higher limits while continuing to use this interface.
Yes. Any audio generated using your Cartesia API key is licensed under your Cartesia developer plan, enabling royalty-free commercial usage for videos, games, ads, and apps.