Retell AI

by Retell AI

Freemium

Voice AI platform for building and deploying conversational phone agents with low latency, pay-per-minute pricing, and developer-friendly API.

4.5
out of 5.0 · 1,400+ reviews
Category Audio & Music
Platform WebAPI
Last Updated May 15, 2026

Overview

Retell AI is a developer-focused voice AI platform for building, testing, and deploying conversational phone agents. It handles the voice pipeline end-to-end — speech-to-text, LLM orchestration, and text-to-speech — so developers can focus on conversation logic rather than audio infrastructure. The result is phone agents that respond with sub-second latency, sounding natural enough for real customer interactions.

The platform supports multiple LLM backends (OpenAI, Anthropic, custom models) and offers pre-built templates for common use cases like appointment scheduling, lead qualification, and customer support triage. Retell’s API-first design means agents can be integrated into existing phone systems, CRMs, and scheduling tools with minimal code.

Retell AI is best suited for developers, agencies, and businesses deploying AI phone agents at scale — from dental offices automating appointment bookings to sales teams qualifying inbound leads. Its 4.8 G2 rating from 1,400+ reviews reflects strong developer satisfaction, though customer support (Discord-only) remains a weak spot.

Pricing

Pay
$0 /mo
  • No platform fee
  • $10 free credits (~60 minutes)
  • 20 concurrent calls included
  • Full platform access with no commitment
Enterprise
$3,000 /mo)
  • Volume discounts drop to ~$0.05/minute
  • Dedicated support, SLA guarantees, and higher concurrency limits. Note: Real production costs run $0.11–$0.15/min including LLM ($0.003–$0.08/min), telephony ($0.015/min), and optional extras
  • Calls under 15 seconds are not billed
  • Additional concurrent call slots cost $8/month each

Pros & Cons

Pros

Sub-second voice latency creates natural conversation flow that callers often can’t distinguish from humans
4.8/5 G2 rating from 1,400+ reviews — one of the highest-rated voice AI platforms available
$10 free credits let developers prototype and test without any payment commitment
API-first design integrates cleanly with existing phone systems, CRMs, and scheduling tools
Supports multiple LLM backends including OpenAI, Anthropic, and custom models

Cons

Customer support is Discord-only — no email or phone support even on paid tiers
Advertised $0.07/min rate is misleading — real costs reach $0.11–$0.15/min with all components
Telephony and LLM costs are separate line items that add up quickly at scale
No native CRM or scheduling integrations — everything requires custom API development
Trustpilot rating of 3.1/5 suggests end-user experience doesn’t always match developer satisfaction

Reviews