The best voice AI platform in 2026 depends on your use case. Vapi is best for API-first developers building outbound SDRs and receptionists at moderate volume. Retell AI is best for HIPAA-regulated industries and teams that need a visual flow editor. LiveKit is best for scale above 10,000 minutes/month, multi-agent architectures, or custom pipelines requiring full control.
The three platforms compared
Vapi
Vapi is a managed voice AI platform with a strong API and developer experience. You configure assistant behaviour in JSON, connect BYOK providers (Deepgram, OpenAI, ElevenLabs), and have an agent live in hours.
Strengths:
- Fastest path to a working agent
- Excellent function calling (CRM integrations via tools)
- Strong outbound dialling capabilities
- Good documentation and active developer community
Limitations:
- Not HIPAA-eligible on lower plans
- Per-minute pricing becomes expensive above 10k minutes/month
- Less suitable for complex branching conversation flows
- Limited real-time call monitoring in the dashboard
Best for: Inbound receptionists, outbound SDR agents, appointment setters, lead qualification. API-first teams. Volumes under 10k minutes/month.
Retell AI
Retell AI sits between Vapi (code-first) and no-code tools. Its visual flow editor lets non-technical teams modify call flows without touching code, while still offering a full API for developers.
Strengths:
- Visual flow editor — non-technical teams can iterate on call flows
- HIPAA-eligible on Business plan with BAA
- State machine conversation model maps well to regulated scripts
- Excellent for compliance-heavy use cases
Limitations:
- Visual flow can become complex for intricate branching
- Slightly higher platform fee than Vapi
- Less flexible for truly novel conversation architectures
Best for: Healthcare, insurance, financial services. Teams where non-technical staff need to maintain call flows. Any use case requiring HIPAA compliance.
LiveKit
LiveKit is an open-source real-time communication framework, not a managed voice AI platform. Building on LiveKit means more engineering work upfront in exchange for full control — lower cost at scale, custom pipelines, and no platform lock-in.
Strengths:
- Lowest cost per minute at scale ($0.07–0.20 vs $0.21–0.33)
- Full pipeline control — swap any component
- WebRTC and SIP support for non-telephony use cases
- Multi-agent orchestration built into the SDK
- OpenAI Realtime API integration for sub-300ms latency
Limitations:
- Requires more engineering expertise
- Higher setup time (days–weeks vs hours)
- You own infrastructure management
Best for: Volume above 10k minutes/month. Multi-agent pipelines. Video + voice combined use cases. Self-hosted / data residency requirements.
Decision matrix
| Requirement | Vapi | Retell | LiveKit |
|---|---|---|---|
| — | — | — | — |
| Ship in under a day | ✓ Best | ✓ | — |
| HIPAA compliance | — | ✓ Best | ✓ (self-hosted) |
| Under 10k min/mo | ✓ | ✓ | — |
| 10k–50k min/mo | ✓ (costly) | ✓ (costly) | ✓ Best |
| 50k+ min/mo | — | — | ✓ Only viable |
| Non-technical team | ✓ | ✓ Best | — |
| Custom pipeline | ✓ Limited | ✓ Limited | ✓ Best |
| OpenAI Realtime API | ✓ | ✓ | ✓ Best |
| Multi-agent | ✓ Limited | — | ✓ Best |
| Video + voice | — | — | ✓ Only |
Cost comparison at key volume thresholds
| Volume | Vapi BYOK | Retell BYOK | LiveKit self-hosted |
|---|---|---|---|
| — | — | — | — |
| 1,000 min/mo | $230–330 | $210–300 | $70–150 |
| 10,000 min/mo | $2,300–3,300 | $2,100–3,000 | $700–1,500 |
| 50,000 min/mo | $11,500–16,500 | $10,500–15,000 | $3,500–7,500 |
Which should you choose?
Choose Vapi if: You’re an API-first developer, you need to move fast, you’re building outbound dialling or a receptionist, and your volume is under 10k minutes/month.
Choose Retell if: You need HIPAA compliance, your team isn’t technical enough to maintain JSON configs, or your use case maps to a structured call script (insurance, healthcare intake, regulated outbound).
Choose LiveKit if: You’re above 10k minutes/month and the cost savings matter, you need custom pipeline components (custom STT models, local LLMs, WebRTC media processing), or you’re building multi-agent architectures.
Most teams start with Vapi or Retell and migrate to LiveKit when they cross 10k minutes/month. That’s the pragmatic path — fast iteration early, cost optimisation later.
See the full comparison: LiveKit vs Vapi and Vapi vs Retell.
Hestur AI builds on all three platforms and recommends the right one for your specific use case. Book a discovery call.