The Stack · Voice, speech & video API

AssemblyAI

Speech-to-text and audio-intelligence API — transcription, diarization, summarization, and LLM-over-audio (LeMUR).

API keyFreemium🔵 agent: self serve instant key

Get API key → instant key, usually no card Docs Website

CategoryVoice, speech & video

TypeAPI service

Authapi-key

PricingFreemium

Agent signup🔵 self serve instant key

SDKsPython, TypeScript, Go, Java, REST

Pricing: $50 free credits, no card; Universal STT $0.15/hr ($0.0025/min); audio-intelligence add-ons priced separately.

🔵 Agents: self serve instant key

Instant self-serve — free signup gives a key immediately (a human unblocks an agent in under 2 minutes).

Free account with $50 credit, no credit card; API key shown immediately in the dashboard. No public signup API.

AssemblyAI — Speech-to-text and audio-intelligence API — transcription, diarization, summarization, and LLM-over-audio (LeMUR).
Website: https://www.assemblyai.com
Docs: https://www.assemblyai.com/docs
Get a key: https://www.assemblyai.com/dashboard/signup
Agent signup: self serve instant key — Free account with $50 credit, no credit card; API key shown immediately in the dashboard. No public signup API.
Auth: api-key
Pricing: freemium — $50 free credits, no card; Universal STT $0.15/hr ($0.0025/min); audio-intelligence add-ons priced separately.
Full record: https://dreaming.press/api/tools/assemblyai.json

Machine record: /api/tools/assemblyai.json

Quickstart

import assemblyai as aai

aai.settings.api_key = "ASSEMBLYAI_API_KEY"
transcript = aai.Transcriber().transcribe("https://assembly.ai/wildfires.mp3")
print(transcript.text)

python · full docs →

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AssemblyAI FAQ

What is AssemblyAI?

AssemblyAI is Speech-to-text and audio-intelligence API — transcription, diarization, summarization, and LLM-over-audio (LeMUR). It's in the Voice, speech & video category of the dreaming.press tool directory.

Is AssemblyAI free?

AssemblyAI is freemium — free to start, paid plans for scale. $50 free credits, no card; Universal STT $0.15/hr ($0.0025/min); audio-intelligence add-ons priced separately..

Can an AI agent sign up for AssemblyAI automatically?

Almost — signup is instant and self-serve (a free key with no sales call), so a human can unblock an agent in under two minutes. Free account with $50 credit, no credit card; API key shown immediately in the dashboard. No public signup API..

Does AssemblyAI have an MCP server?

AssemblyAI does not publish an official MCP server as of our last check.

Is AssemblyAI open source?

AssemblyAI is a hosted API service, not an open-source project.

What languages does AssemblyAI support?

AssemblyAI offers Python, TypeScript, Go, Java, REST.