Retell AI
intermediateBuild, test, and deploy AI voice agents in hours, not months.
Retell AI is a developer-first voice agent platform that makes it surprisingly fast to build phone-based AI agents. You bring the LLM logic (OpenAI, Claude, custom) and Retell handles telephony, turn-taking, interruption handling, and ultra-low latency voice synthesis. The result is phone conversations that feel natural — no awkward pauses or robotic responses. Businesses use Retell for appointment scheduling, lead qualification, outbound campaigns, and after-hours support. PxlPeak builds Retell-powered voice agents with custom conversation flows, CRM integrations, and real-time analytics.
< 800ms
Voice-to-voice latency
500+
Companies building on Retell
15M+
Minutes of AI calls processed
20+
Languages supported
Key Features
Sub-800ms voice-to-voice latency for natural conversations
Bring-your-own-LLM architecture (OpenAI, Anthropic, custom)
Built-in telephony with call transfer, voicemail, and conferencing
Interruption handling and natural turn-taking
Real-time conversation analytics and sentiment tracking
Multi-language support with automatic language detection
Use Cases We Implement
Build AI receptionists that schedule appointments and answer FAQs
Run outbound lead qualification calls at scale
Provide after-hours support without staffing a night shift
Automate insurance claim intake and initial triage calls
How We Implement Retell AI
Assess
We analyze your business needs and how Retell AI fits into your workflow.
Configure
Set up Retell AI with custom settings, integrations, and data connections.
Integrate
Connect to your existing tools — CRM, helpdesk, email, and more.
Train & Launch
Train your team, document everything, and provide ongoing support.
Frequently Asked Questions
How is Retell AI different from Bland.ai or Vapi?
Retell focuses on developer experience and latency. Bland.ai is more turnkey (less customization but faster setup). Vapi sits in between. Retell gives you the most control over the LLM layer, which matters for complex conversation flows.
What LLMs work with Retell AI?
Any LLM with a REST API. Most customers use GPT-4o or Claude for the conversation logic. Retell handles the voice layer — you own the intelligence layer entirely.
Can Retell AI transfer calls to human agents?
Yes. Retell supports warm transfers with context handoff, cold transfers, and conference bridging. The AI can summarize the conversation before transferring so the human agent has full context.
How much does a typical Retell AI deployment cost?
Voice costs run $0.07-0.14 per minute depending on your plan. Add LLM costs (roughly $0.01-0.03 per minute for GPT-4o). A business handling 1,000 calls/month at 3 minutes each would pay roughly $250-500/month in platform costs.
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