Deepgram vs AssemblyAI: Which Speech API Should Developers Use?
Deepgram offers real-time voice AI APIs for speech-to-text, text-to-speech, and voice agents. AssemblyAI focuses on speech-to-text and audio intelligence APIs such as diarization, summarization, sentiment, and entity extraction.
Tagline
Voice AI APIs for speech-to-text, text-to-speech, and agents.
Speech AI models for transcription and audio intelligence.
Pricing
FreemiumFree credits; usage-based pricing
FreemiumFree credits; usage-based pricing
Open source
No
No
API available
Yes
Yes
Platforms
API, Cloud, Self-hosted
API
Key features
- • Speech-to-text API
- • Text-to-speech API
- • Voice Agent API
- • Audio intelligence
- • Real-time streaming
- • Speech-to-text API
- • Speaker diarization
- • Audio summarization
- • Sentiment analysis
- • Entity detection
Deepgram
Voice AI APIs for speech-to-text, text-to-speech, and agents.
Pros
- + Low-latency developer APIs
- + Voice agent infrastructure
- + Cloud and self-hosted options
Cons
- – Developer integration required
- – Costs scale with usage
- – Not a no-code tool
AssemblyAI
Speech AI models for transcription and audio intelligence.
Pros
- + Developer-first speech API
- + Good audio intelligence features
- + Usage-based pricing
Cons
- – API-only for most workflows
- – Costs scale with volume
- – Requires engineering integration
Which should you choose?
Choose Deepgram if…
- • You need voice agents
- • You need call transcription
- • You need speech analytics
Choose AssemblyAI if…
- • You need transcription
- • You need audio analytics
- • You need voice product development
The verdict
Choose Deepgram for low-latency voice applications, voice agents, and real-time speech infrastructure. Choose AssemblyAI when your main workflow is transcription plus audio intelligence for recorded or batch audio.