AssemblyAI
(USA) A leading API company for advanced Speech-to-Text, offering highly accurate transcription, summarization, and audio intelligence.
- Freemium
- API, Web
- WritingAI Tools for TranscriptionAI Speech-to-Text
- Free plan available
- No credit card

What is AssemblyAI?
Key features
Speech-to-text transcription
converts audio files and live streams into written text with word-level timestamps
Speaker detection
identifies different speakers in a recording and labels who said what
Auto-summarisation
generates concise summaries of longer transcripts
Entity recognition
identifies and flags important information like names, dates, and topics mentioned in speech
Sentiment analysis
determines the emotional tone of speaker statements
Custom vocabulary
allows you to add domain-specific words or terminology for more accurate results
Pros & cons
Advantages
- High accuracy across different audio qualities, accents, and languages
- Simple REST API integration means you can add speech processing to existing applications without major rebuilds
- Additional intelligence features beyond basic transcription, such as summarisation and topic detection
- Freemium tier lets you test before spending money
- Fast processing times suitable for both batch and real-time use cases
Limitations
- API-only approach means you need development work to use it; there is no simple web interface for casual users
- Costs can add up quickly if you are processing large amounts of audio regularly
- Quality depends on audio input; poor quality recordings still produce less accurate results
Use cases
Transcribing customer support call recordings for quality assurance and compliance
Converting recorded interviews or podcasts into searchable text archives
Generating captions or subtitles for video content
Analysing meeting recordings to extract action items and decisions
Building voice-activated features into mobile or web applications
Ready to try AssemblyAI?
Pricing
Free
Free
Limited monthly transcription minutes to trial the service; access to core transcription features
Pay-as-you-go
Variable
Charged per minute of audio processed; access to all transcription and intelligence features; no minimum commitment
Custom Enterprise
Contact sales
Volume discounts, dedicated support, custom integrations, and service level agreements for organisations with high usage
Get started with AssemblyAI
Click through to AssemblyAI and start using it now.
- Free plan available
- No credit card