AssemblyAI by AssemblyAI
Speech-to-text API (batch and streaming) with diarization, speech understanding and voice agents.
Voice (speech-to-text Official MCP server
Price
Free plan
list price
Free tier
Yes
Up to 185 hours pre-recorded and 333 hours streaming...
SDK downloads
1.3M
npm assemblyai · PyPI assemblyai
Status
Up
6 incidents in 30 days
Pricing
| Free tier | Up to 185 hours pre-recorded and 333 hours streaming transcription, no credit card |
|---|---|
| Cheapest paid plan | — |
| Usage price | Universal-2 $0.15/hour; Universal-3.5 Pro $0.21/hour; Universal-Streaming $0.15/hour; diarization +$0.02/hour |
| Good to know | Pay as you go, no subscription; custom enterprise rates. The official MCP server is a docs-lookup server only (searches AssemblyAI documentation), not an API-calling server. Voice Agent API $4.50/hour. |
From the official pricing page, checked Oct 9, 2026. Prices change: confirm before you buy.
Use it from an agent
| MCP server | Official: https://assemblyai.com/docs/mcp |
|---|---|
| npm | npm install assemblyai |
| PyPI | pip install assemblyai |
| GitHub | AssemblyAI/assemblyai-python-sdk · 213 stars · last push Sep 29, 2026 |
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