AssemblyAI vs OpenAI Realtime API

Comparing the features of AssemblyAI to OpenAI Realtime API

Feature
AssemblyAI
OpenAI Realtime API

Capability Features

Auto-Language Detection
Enterprise Privacy Commitment
Expanded Model Support Planned
Five New Voices
5
Function Calling
Human and Automated Safety Monitoring
Industry Leading Accuracy
Interruption Handling
Keyterms Prompting
No Training on Data Without Permission
No-Code Playground
Playground Access
Preferred by End Users
Preferred by 73% of end users
Prompt Caching Planned
Public Beta
Reduced Hallucinations
Up to 30% less
Reference Client Available
Scalable Platform
Six Preset Voices
6
Smart Formatting
Speaker Diarization
Speech Understanding
Speech-to-Speech
Speech-to-Text
Streaming Audio Inputs/Outputs
Supported Audio Types
Pre-recorded and streaming audio
Supports Text and Audio Inputs
TextAudio
Ultra Low Latency
WebSocket Connection

Integration Features

Agora Integration
API Integrations
Chat Completions API Integration
LiveKit Integration
OpenAI Node.js SDK Planned
OpenAI Python SDK Planned
Platform Integrations
API
Supports GPT-4o
gpt-4o-realtime-preview
Twilio Voice API Integration

Limitation Features

AI Disclosure Requirement
Audio Only Modality (Initially)
Lower Session Limits Tiers 1-4
Lower than 100
No Explicit Feature Limits
No Simultaneous Session Limit Anymore
No Throttling
Simultaneous Sessions Limit Tier 5
100
Usage Policy Restriction

Pricing Features

Approximate Audio Input Price
$0.06/minute
Approximate Audio Output Price
$0.24/minute
Free API Trial
No Contracts
No Free Tier
Pay as you go pricing
Pricing Audio Input
$100/1M tokens
Pricing Audio Output
$200/1M tokens
Pricing Cached Audio Input
$20/1M tokens
Pricing Cached Text Input
$2.50/1M tokens
Pricing Text Input
$5/1M tokens
Pricing Text Output
$20/1M tokens