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Ultravox.ai
✓ verifiedFreemium

Speech-native voice AI infrastructure and APIs for developers building low-latency, natural-sounding conversational voice agents.

1.9K saves
Pricing
Pay Go: $0/month (5 cents per minute including TTS, up to 5 concurrent calls)
Pro: $100/month billed yearly (no hard concurrency caps)

Free trial available

Core features
  • Speech-native model that processes audio directly without transcription bottleneck
  • Neural voice activity detection for natural turn-taking
  • REST APIs and SDKs for web and mobile integration
  • Built-in telephony provider integrations
  • Self-managed inference stack for low latency at scale
  • Open-weight core models available on Hugging Face
Use cases
  • Building real-time conversational voice agents for customer support
  • Adding voice interfaces to existing applications
  • Powering telephony-based AI voice assistants
  • Research and experimentation with speech-native AI models
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