Retell AI
API For Building Human-like Conversational Voice AI
FreeVoice6,057 impressions#12 of its week
Retell AI provides an API to build human-like conversational voice agents for phone, chat and SMS with low latency.
- for
- Developers building voice-based customer service, sales or support automation.
- pricing
- freemium · free trial
Key features
- Drag-and-drop flow builder — Design complex call workflows visually with functions, integrations and DTMF handling.
- Real-time testing & simulation — Manually test, simulate thousands of scenarios and run regression tests before deployment.
- Ultra-low latency — Proprietary orchestration delivers ~600 ms response time for smooth conversations.
- Multi-channel support — Deploy agents over voice calls, web/chat widgets and SMS via a unified API.
- Enterprise security — HIPAA, SOC 2 Type II, GDPR, ISO 27001 compliance with SSO, role-based access and data redaction.
- Pay-as-you-go pricing — No contracts; $0.07-$0.31 per minute for voice agents and $0.002 per chat message.
Use cases
- Receptionist answering and routing inbound calls
- Appointment scheduling via phone or SMS
- Lead qualification and outbound dialing campaigns
- Customer service with AI-human handoff
- Debt collection and automated surveys
Retell AI vs alternatives
 Retell AI |  Voice Calling SDK by Dyte |  Layercode CLI |  VoAgents | .png?width=64) Foni | |
|---|---|---|---|---|---|
| Best for | Low-latency AI voice agents for phone calls | Voice calling SDK | CLI-based voice AI | AI voice assistants | Business AI caller |
| Pricing | Freemium | Subscription | Subscription | Subscription | Subscription |
| DevHunt upvotes | 4 | 44 | 13 | 1 | 0 |
| Launched | May 2024 | May 2024 | Oct 2025 | Sep 2026 | Jan 2024 |
- Retell AI vs Voice Calling SDK by Dyte: Dyte provides a low-level voice SDK for raw call handling, not a full AI agent platform.
- Retell AI vs Layercode CLI: Layercode CLI focuses on building voice AI agents from the terminal, lacking visual flow builder and enterprise compliance.
- Retell AI vs VoAgents: VoAgents offers AI voice assistants but does not emphasize low-latency phone call orchestration or extensive compliance features.
- Retell AI vs Foni: Foni is a ready-made AI caller for businesses, whereas Retell gives developers full API control and custom workflow design.
Retell AI FAQ
How does Retell AI handle interruptions?+
Its proprietary turn-taking model detects mid-sentence interruptions and switches to listening without waiting for a pause.
What is the latency of the voice agents?+
Independent benchmarks show an average latency of about 600 ms, keeping conversations fluent.
Is there a free tier?+
Yes – new users receive $10 in free credits and 20 concurrent calls with full platform access.
How is usage billed?+
Calls are billed per second to the nearest second; only connected call time is charged, including silence while the engine listens.
Can I connect my own phone number?+
Yes – Retell supports any telephony system via SIP trunking, allowing you to use existing numbers.
What compliance certifications does Retell have?+
Retell is HIPAA, SOC 2 Type II, GDPR and ISO 27001 certified and offers SSO, PII redaction and custom data-retention options.
Summarized by DevHunt from retellai.com · Sep 28, 2026. Details may change; check the official site.
