Vapi
Free tierVoice agents for builders
Free tier available·All audiences·Powered by OpenAI (intelligence), Deepgram (transcriber), ElevenLabs (voice)·API available
Key strengths
Sub-500ms average latencyEnterprise-grade scalability (billions of calls)SOC 2, HIPAA, and PCI complianceAPI-native designFully managed infrastructureReal-time monitoring and observabilityBroad telephony integrations (Twilio, Vonage, Telnyx, SIP)
Free tier + paid plans
Founded 2023
No ratings yet
Vapi — Technical Overview
Vapi is an API-native voice agent platform built for developers and enterprises who need to design, deploy, and scale conversational voice AI. Founded in 2023, Vapi abstracts the full voice pipeline — transcription, intelligence, and synthesis — into a single managed infrastructure layer.
Architecture & Stack
- Transcription: Deepgram
- Intelligence: OpenAI
- Voice synthesis: ElevenLabs
- Transport: WebSockets, WebRTC, and SIP for flexible inbound/outbound call routing
- Telephony integrations: Twilio, Vonage, Telnyx
Performance & Scale
- Sub-500ms average end-to-end latency
- Designed for enterprise-grade scalability (billions of calls)
- Fully managed infrastructure — no self-hosting required, though the project is open source (126 GitHub stars)
Compliance & Security
- SOC 2, HIPAA (add-on), and PCI compliant
- OAuth2, SSO, and RBAC support for access control
Pricing
- Free tier: $5 credits included
- Usage-based: $0.05/min (Vapi hosting); model costs passed through at cost
- Core: $29/mo | Pro: $999/mo minimum (10% of Vapi hosting fee) | Premier: custom
- Add-ons: HIPAA compliance ($2,000/mo), additional concurrency ($10/line/mo), additional organizations ($20/org/mo)
Real-time monitoring and observability are included across tiers.