AssemblyAI

AssemblyAI

AssemblyAI provides developer-focused speech-to-text and voice AI APIs, including pre-recorded transcription, real-time streaming, and voice agent infrastructure.

assemblyai.com · 🔄 Last updated Jun 26, 2026
Try AssemblyAI → ✓ Free plan available
Trust Score: 86 Editorial estimate Freemium Free tier available Transcription Trending
⚡ At a glance

Best for: Developers and engineering teams building voice AI products, transcription pipelines, call analytics, AI notetakers, or voice agents

✓ Industry-leading transcription accuracy with the new Universal-3.5 Pro Realtime model

✗ Pricing can escalate quickly at high audio volumes — cost-sensitive teams may find it expensive at scale

An honest editorial snapshot from this tool's profile — not a paid placement.

AssemblyAI offers a suite of speech AI APIs trusted by millions of developers, covering pre-recorded and real-time transcription, speech understanding, and voice agent capabilities. Its latest Universal-3.5 Pro Realtime model is the first streaming STT model that accepts the agent's question as context input. The platform targets builders who need scalable, accurate, and low-latency voice AI without managing their own model infrastructure.

Best for: Developers and engineering teams building voice AI products, transcription pipelines, call analytics, AI notetakers, or voice agents

Key Features

  • Pre-recorded Speech-to-Text API
  • Real-time streaming Speech-to-Text API (Universal-3.5 Pro Realtime)
  • Speech Understanding API (summarization, sentiment, entity detection)
  • Voice Agent API
  • LLM Gateway and Guardrails
  • Self-hosted and cloud deployment options
  • Medical transcription support
  • Speaker diarization
  • Multi-language transcription

How to use AssemblyAI

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See how AssemblyAI compares side-by-side with similar tools

AssemblyAI
AssemblyAI Current
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Rating ★★★★½ 4.3 ★★★★☆ 4.2 ★★★★☆ 4.2 ★★★★☆ 4.1
Trust Score 86/100 84/100 84/100 82/100
Pricing
Free $0
Pay as you go From $0.15/hour to…
Enterprise / Custom Custom
Free $0/mo
Essentials $25.49
Pro $47.99
Unlimited Custom
Open Source (Self-Hosted) Free
OpenAI API - Transcription From $0.003/minute…
Realtime Speech-to-Text API $0.017/minute
Pay As You Go $10/hour
Core $25/mo
Advanced $50/mo
Pro $80/mo
Data updated 1 month ago 1 month ago 1 month ago 1 month ago
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About Trust Score

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