Overview
AssemblyAI is a developer-focused speech AI platform providing best-in-class transcription alongside a suite of audio intelligence features. Beyond accurate speech-to-text, it offers speaker diarization, sentiment analysis, topic detection, PII redaction, and real-time streaming — making it the most complete audio AI API available.
Key Features
- Universal-2: state-of-the-art transcription model with 95%+ accuracy
- Speaker Diarization: identifies and labels who said what
- Real-time streaming transcription with sub-300ms latency
- Sentiment Analysis, Entity Detection, and Auto Chapters
- PII Redaction for compliance use cases
- LeMUR: apply LLMs to audio files for summarization and Q&A
- SDKs for JavaScript, Python, Go, Java, and .NET
Pricing: Free tier (100 hours/month transcription); pay-as-you-go after; premium features priced separately.
Pros
- Best-in-class transcription accuracy among API providers
- Rich audio intelligence features beyond just transcription
- LeMUR bridges audio and LLM in a single API call
- Generous free tier for development and testing
Cons
- Production pricing can exceed Whisper self-hosting at scale
- Real-time streaming adds latency vs batch transcription
- Some intelligence features add cost per minute
Tags
Product Updates
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