AsyncAI Voice API vs Retell AI

Comparing the features of AsyncAI Voice API to Retell AI

Feature
AsyncAI Voice API
Retell AI

Capability Features

Advanced Speech Features
emotional inflectionrhythm controlmultilingual support
Agent Builder
Agent Testing
API Access
API Sample Rate Support
44100
API Streaming
Appointment Scheduling
Audio AI Features
end-to-end editingnoise cancellationAI-powered refinement
Auto-Sync Knowledge Base
Automatic Scalability
Millions of concurrent calls
Batch Calls
Branded Caller ID
Call History
Call Monitoring
Call Transfer Options
Comprehensive Documentation
Creative Suite Tools
PodcastingVideo AIAudio AIVoice AI
Edge Case Handling
Global Reach
Industry Compliance
SOC 2 Type 1&2HIPAAGDPR
Infinite Voice Styles
Infinite
Lifelike Text-to-Speech
LLM-Powered
Low Latency
500ms latency
Multi-language Support
18+ languages
Multiple Deployment Channels
AI phone callsWeb callsSMSChat
Natural Language Conversations
Navigate Through IVR
No Concurrency Limits
Platform Uptime
99.99% uptime
Podcasting Features
audio enhancementnoise reductionvoice conversion
Quick Implementation
<10 minutes
Supported Language List
20+
Supported Use Cases
Customer ServiceGame DevelopmentDigital MarketingDigital PublishingPatient CommunicationConversion OptimizationConversational AI / AgentsGlobal ReachDigital Humans / AI AvatarsSupply ChainTalent AcquisitionInclusive Design
Uptime and Reliability
Verified Phone Numbers
Video AI Features
intelligent video editingautomatic captioningvisual enhancement
Voice AI Tools
text-to-speechvoice cloning
Voice Cloning
Voice Cloning Sample Duration
3
Voice Library
1000
Voice Model Version
asyncFlow v1.0
Voice Output Emotional Styles
ExcitedNeutralWarm
Voicemail Detection

Integration Features

API Implementation Languages
PythonJavaScriptcURL
API Output File Formats
WAVraw PCM (pcm_f32le)
CRM/Automation Integrations
Cal.comn8nGoHighLevelTwilioVonageOpenAI
Integrates with Any CRM
Integrates with Any Telephony
Integrates with Automation Platforms
Integrates with Databases
Platform Integrations
APIPythonJavaScriptcURL
Telephony Integration
TwilioVonageTelnyxPlivoRingCentral

Limitation Features

API Key Integration
No Desktop App Mentioned
No Mentioned Self-hosting
No Pricing Information
No Public Pricing Listed
No Usage Quotas Stated

Pricing Features

Developer-friendly Pricing
Developer-friendly
Free Tier
Pricing Plan Details