#1 real-time speech models and voice agents.

Purpose-built for developers. One API with no tradeoffs between quality and speed.

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Join the teams making the switch to Cartesia

Artificial Analysis

Ranked #1

in Speech Arena leaderboard & Speech to Text leaderboard by Artificial Analysis

The full stack for interactive intelligence

Speech models and the voice agents built on them, running on State Space Models for low latency at scale.

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Ink.Speech-to-text

The fastest, most accurate streaming transcription model.

Sonic.Text-to-speech

The fastest, ultra-realistic voice synthesis model.

Voice agents as fast and accurate as the models powering them

Managed Agents platform interface
Managed Agents.AI voice agents for phone calls

The fastest, most customizable platform for building and shipping enterprise voice agents, powered by our models.

Pioneering AI research:Architectures that learn through real-world interaction

Our team has pioneered breakthrough AI architectures, including state space models (SSMs), Mamba & H-Nets. Our research manifests our mission — we architect AI that learns from and interacts with the world like humans do.

Our research

Deploy AI anywhere.Own it everywhere.

The same models and agents across cloud, on-premise, and on-device. Inference runs in-region — keeping you within your latency envelope, data residency obligations, and compliance frameworks.

Deploy via regional API endpoints across the globe — ensuring in-region processing, high availability, and the uptime your production systems demand.

On-device deployment tileOn-device deployment tileOn-premise deployment tileOn-premise deployment tileCloud deployment tileCloud deployment tile

Trusted by leading enterprises. Speaking from experience.

Discover success stories
“Cartesia’s state-space models bring enterprise-grade speed and quality to our AI Voice Agents… making it possible for businesses to deploy secure, scalable voice agents that can understand, act, and adapt in real time.”

Ravi Krishnamurthy

VP Product

“With Cartesia's Sonic model, users can interact with a wide range of high-quality, human-like voices in multiple languages, enhancing their experience on our platform.”

Spencer Chan

Head of Poe Product

“Cartesia is leading the charge of building efficient, multimodal models from first principles, starting with their Sonic TTS model.”

Vipul Ved Prakash

CEO

“We didn’t switch to Sonic because it was incrementally better, we switched because nothing else came close… we’ve seen a 2.9% lift in our conversion and a 12.2% increase in customer engagement.”

Akshay Ramaswamy

Staff Product Manager

“Sonic represents a significant evolution over previous TTS models, delivering refined prosodic rhythm, natural intonation, superior pacing and wider emotional range for more “human” sounding voices.”

Tyler Brown

Voice Expert

“Cartesia Sonic is the best voice model today for real-time multimodal use cases.”

Kwindla Hultman

CEO