Cartesia
Cartesia
Cartesia is the category leader for real-time voice AI applications — voice agents, IVR systems, conversational AI, and live phone interfaces where latency is the critical constraint. Sonic 2 achieves sub-100ms time-to-first-audio-byte, making it the fastest production-grade TTS model available. Instant voice cloning from just 3 seconds of audio — the lowest sample requirement in the category. Pricing: free tier for personal use; Growth plan ~$99/month; enterprise custom. API at ~$50/1M characters. 2026 market split recognized Cartesia as the primary pick for real-time agent use cases over ElevenLabs (better for long-form narration) and Deepgram (better for enterprise volume).
Free: personal use (limited). Growth: ~$99/mo. Enterprise: custom. API: ~$50/1M characters. Per-character pay-as-you-go available.
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