Video to Knowledge Base

AssemblyAI

6.4

cloud diarization

Best-in-class cloud STT API with strong diarization and LLM features — but cloud-only and developer-oriented.

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Score breakdown

Weighted by our published rubric. Overall: 6.4/10.

Accuracy (WER) 20%
9
Privacy / on-prem 20%
3
Diarization 10%
9
RAG / agent-readiness 20%
6
Integrations 10%
6
Pricing / value 10%
7
Ease of use 10%
6

Pros & cons

Pros

  • High accuracy + in-house diarization across 95+ languages
  • LeMUR LLM features (summaries, Q&A) layered on the transcript

Cons

  • Cloud-only — not for privacy/compliance-bound audio that must stay local
  • A developer API, not a finished product or UI

AssemblyAI is a developer-focused speech-to-text API with strong accuracy, in-house speaker diarization and a LLM layer (LeMUR) for summaries and Q&A. Closest of the cloud APIs to an “agent-ready” story — but it still runs in AssemblyAI’s cloud.

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