OpenAI Realtime API vs UntitledPen

Comparing the features of OpenAI Realtime API to UntitledPen

Feature
OpenAI Realtime API
UntitledPen

Capability Features

AI Writing Commands
rewritepolishimprove flowtone
Audio Download Quality Free Plan
128 kbps, 44.1 kHz
Audio Download Quality Paid Plans
Up to 192 kbps, 44.1 kHz
Audio Exports
Customizable Voice Tone
Enterprise Privacy Commitment
Expanded Model Support Planned
File Upload Support
Five New Voices
5
Function Calling
Human and Automated Safety Monitoring
Interruption Handling
Mini Demo Available
Multilingual Support
Natural Voice Generation
No Training on Data Without Permission
Notion-like Smart Editor
Playground Access
Prompt Caching Planned
Public Beta
Reference Client Available
Six Preset Voices
6
Smart Transcription
Smart Writing Assistant
Speech to Text
Speech-to-Speech
Streaming Audio Inputs/Outputs
Studio Mode
Supports Text and Audio Inputs
TextAudio
Text to Speech
Ultra Low Latency
Voice Editor
Voice Types
AlloyAshBalladCoralEchoFableNovaOnyxSageShimmerVerse
WebSocket Connection

Integration Features

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

Limitation Features

AI Disclosure Requirement
Audio Only Modality (Initially)
Audio Quality Limitation Free
128 kbps max
Audio Quality Limitation Paid
192 kbps max
Character Limit
500
Free Plan AI Usage Limit
1000
Free Plan Voice Generation Limit
10000
Lower Session Limits Tiers 1-4
Lower than 100
No Simultaneous Session Limit Anymore
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
Creator Plan Monthly Price
$25 per month
Free Plan AI Refine Limit
1000
Free Plan Character Limit
10000
Free Plan Price
$0
Free Tier
No Credit Card Required
No Free Tier
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
Pro Plan Price
$12 per month (billed annually)
Pro/Creator Plan Character Limit
200000
Trial Period
Not specified