Cartesia vs Ultravox: Which Is Better for Your Team in 2026?
Cartesia and Ultravox are both used for ai voice agents. Below we compare them on pricing, AI capabilities, compliance, and the use cases each one fits best — all from verified vendor data.
Choose Cartesia if…
- Voice agent platform builders (Vapi, Retell, LiveKit) embedding best-in-class TTS/STT as a component
- Enterprise teams in healthcare and finance who need HIPAA + PCI compliance with sub-100ms latency
- Teams building multilingual agents across 42 languages including Indian-language markets
- Developers who want to own the full stack via Line and avoid LLM and telephony lock-in
Choose Ultravox if…
- Developer teams building voice agents who want to eliminate the 3-stage ASR→LLM→TTS pipeline overhead
- Open-source-first engineering teams who want to evaluate or self-host the model weights before committing to the managed API
- Startups needing a fast path to PSTN voice agents with built-in Twilio/Telnyx/Plivo and no infrastructure work
- Teams building on Pipecat or LiveKit who want a drop-in speech-to-speech service with the best benchmark scores
Cartesia vs Ultravox: feature comparison
| Feature | Cartesia | Ultravox |
|---|---|---|
| At a glance | ||
| Category | AI voice agent platform | AI voice agent platform |
| Best fit | Smb, Mid market, Enterprise | Smb, Mid market, Enterprise |
| Deployment | Cloud, Private cloud, On premise | Cloud, Self hosted |
| Channels | Voice, Web chat | Voice |
| Pricing & ratings | ||
| Starting price | Contact sales | From $0.05/min |
| Free trial | No | No |
| User rating | — | — |
| AI capabilities | ||
| Autonomous voice agent | Yes | Yes |
| Real-time agent assist | No | No |
| Conversation intelligence | No | No |
| Automated QA | No | No |
| Intelligent routing | No | No |
| Compliance | ||
| SOC 2 Type II | Yes | No |
| HIPAA | Yes | No |
| PCI DSS | Yes | No |
| GDPR | Yes | No |
Cartesia vs Ultravox: frequently asked questions
- What is the difference between Cartesia and Ultravox?
- Fastest TTS/STT infrastructure in the category — Sonic-3 at 90ms, Ink at 66ms TTCT. Line adds a full agent layer on top. Infrastructure-first but increasingly a finished platform. By contrast, Speech-native LLM with a managed API — Ultravox v0.7 (GLM 4.6) skips ASR and TTS stages entirely. #1 on VoiceBench. Developer-only; no no-code builder; compliance certs unconfirmed.