Cartesia vs PolyAI
A side-by-side comparison of capabilities, autonomy, integrations, and pricing to help you choose.
Short answer: choose Cartesia if you want low-latency voice ai models and a platform for real-time voice agents (Assistant, freemium); choose PolyAI if you want enterprise voice ai agents that answer and resolve customer calls (Supervised agent, usage).
| Cartesia | PolyAI | |
|---|---|---|
| What it is | Low-latency voice AI models and a platform for real-time voice agents | Enterprise voice AI agents that answer and resolve customer calls |
| Type | platform | platform |
| Autonomy | Assistant | Supervised agent |
| Pricing | freemium · Free (20K credits/mo); Pro $5/mo | usage |
| Best for | developers, enterprise | enterprise, mid-market |
| Deployment | saas, api, self-hosted, on-prem | saas, api |
| Modalities | text, voice, api, code | voice, text, api |
| Models | proprietary | proprietary |
| Protocols | rest-api, function-calling | mcp, rest-api, function-calling |
| Integrations | LiveKit, Twilio, Pipecat, Vapi | Five9, NICE CXone, Twilio, Amazon Connect, Genesys, Salesforce |
| Capabilities | 4 documented | 4 documented |
Cartesia
- +Genuinely differentiated state-space-model tech with best-in-class latency and on-device efficiency
- +Full stack (TTS, STT, cloning, and the Line agent platform) plus deep ecosystem integrations and self-hosted/VPC options
- +Strong technical credibility and capital, including NVIDIA backing
- -Younger and less battle-tested than ElevenLabs and Deepgram; the Line agent platform is barely a year old
- -Closed, proprietary models (no open weights for production Sonic/Ink), creating lock-in
PolyAI
- +Strong, natural voice quality proven on hard and regulated call types
- +Deep CCaaS and CRM integration plus a proprietary model stack with enterprise compliance
- +Real enterprise traction and NVIDIA backing
- -Opaque, high-floor pricing inaccessible to SMBs
- -Historically heavy managed-service implementation; the self-serve story is newer
Which should you choose?
Cartesia is low-latency voice ai models and a platform for real-time voice agents, best for developers, enterprise. PolyAI is enterprise voice ai agents that answer and resolve customer calls, best for enterprise, mid-market. The right choice depends on the autonomy level you want, your existing integrations, and your budget, all compared above.
This comparison is generated from the sourced Cartesia and PolyAI profiles. Open either profile to review its evidence and last-reviewed date.