78
Stack Score
Best for
Developers and startups building production voice AI products who need infrastructure flexibility over no-code simplicity.
At a glance
- Pricing
- freemium
- Setup time
- 1 hour
- Learning curve
- steep
- Last verified
- 5/19/2026
What we love
- ✓Best developer experience for shipping voice agents fast
- ✓Bring-your-own everything — no model lock-in
- ✓Telephony, web, and mobile all from one platform
- ✓Active community and rich sample apps
Where it falls short
- −Per-minute pricing stacks (LLM + STT + TTS + Vapi) — costs grow fast
- −Tuning latency under 500ms requires real expertise
- −Less hand-holding than Bland or Retell at the no-code layer
Pricing
✓ Pricing verified Jun 21, 20262 tiers
Build
$0.05
per minute of call usage
- ✓Usage-based call minutes
- ✓10 included call concurrency + $10/line/mo
- ✓$0.005 per SMS/chat message
- ✓Model provider cost at-cost (or $0 with BYOK)
- ✓14 day call history, 30 day chat history
Scale
Custom
annual contract
- ✓Volume-based pricing on calls and SMS
- ✓Custom call concurrency
- ✓Custom data retention
- ✓SSO, RBAC, SOC2 included
- ✓Named support engineer and account manager
Why we picked it
When you're building a real voice agent (not just demoing one), Vapi handles the plumbing.
Overview
Developer platform for building voice agents — bring your own LLM, TTS, ASR. Pay per minute of conversation.
Key features
- ●Voice agent infrastructure — STT, LLM, TTS in one orchestration
- ●Sub-700ms latency end-to-end on optimized stacks
- ●Bring-your-own LLM, voice provider, and STT
- ●Built-in telephony via Twilio, Telnyx, Vonage
- ●Function calling and tool use for agent actions
- ●Web SDKs and server-side APIs for integration
- ●Call recording, transcription, and analytics dashboard
Best use cases
Inbound support automation
Answer tier-1 support calls 24/7 with an agent that pulls from your knowledge base and escalates to humans on demand.
Outbound qualification
Place outbound dials at scale for survey, scheduling, or lead qualification with sub-second responses.
In-app voice copilot
Embed a voice agent in your product so users can ask, navigate, and take actions hands-free.
Integrations
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