Cartesia
Ultra-low-latency real-time voice generation for AI agents
About Cartesia
Cartesia is an AI audio and voice intelligence company that powers conversational AI agents and interactive applications with ultra-low-latency, hyper-realistic voice synthesis. Its flagship State Space Model (SSM) architecture, Sonic, delivers human-like voice generation with sub-90ms time-to-first-audio latency. While traditional transformer-based text-to-speech models struggle with high latency and compute overhead, Cartesia's lightweight SSM architecture allows developers to build fluid, conversational voice bots that feel instantaneous and natural, without awkward pauses. Cartesia is used by developers, contact centers, game studios, and AI agent builders across the world to power real-time phone assistants, gaming NPCs, live transcription translation, and voice-enabled enterprise interfaces.
Cartesia's Sonic engine is built on state space foundation models designed specifically for continuous streaming audio. It supports multilingual voice cloning from a 5-second sample, fine-grained emotional control (whisper, excitement, professional demeanor), and dynamic pacing adjustments. Developers can integrate Cartesia via WebSocket and REST APIs, Python and TypeScript SDKs, and WebRTC streaming for mobile and browser applications. The platform handles concurrent high-throughput workloads with strict SLA guarantees.
Sign up at cartesia.ai and generate your API key.
Choose from the library of pre-built voices or clone a custom voice using a 5-second sample.
Connect your backend to Cartesia's WebSocket or REST API endpoints using Python or TypeScript SDKs.
Stream text tokens directly into Cartesia and receive real-time audio chunks in <90ms.
Deploy voice agents with WebSockets or WebRTC for phone bots, web apps, or games.
Capabilities & Features
Common Use Cases
real-time-voice-agents
voice-cloning
conversational-ai
interactive-gaming-npcs
customer-support-bots
Frequently Asked Questions
How fast is Cartesia's voice synthesis latency?
Cartesia's Sonic model achieves a time-to-first-audio latency of under 90ms, making it fast enough for real-time human-agent voice conversations.
Can I clone my own voice with Cartesia?
Yes, Cartesia supports instant voice cloning using a short 5-second audio sample via their web playground or API.
How does Cartesia compare to ElevenLabs?
While ElevenLabs excels at long-form audio and studio narration, Cartesia is optimized specifically for ultra-low latency real-time voice bots and agent streaming.
Free Plan
Free starter tier includes $5 in API credits and access to the web playground.
Paid Plan
Pay-as-you-go pricing at ~$0.01 per minute of generated audio. Team and Enterprise plans offer dedicated infrastructure, custom voice design, and volume discounts.
Pros & Cons
Ultra-low latency under 90ms — ideal for conversational voice agents
Instant zero-shot voice cloning from just a 5-second audio clip
State Space Model architecture yields superior efficiency and quality
Full WebSocket, REST, Python, and TypeScript SDK support
Multilingual support with expressive emotion and cadence modulation
Primarily designed as an API-first tool for developers rather than non-technical creators
Requires streaming architecture knowledge to maximize low-latency performance
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