AssemblyAI

Transform speech into meaning with one robust API

4.8•32 reviews•

5.6K followers

Transform speech into meaning with one robust API

4.8•32 reviews•

5.6K followers

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Unified API

•

AI Infrastructure Tools

Build new AI products with voice data leveraging AssemblyAI’s industry-leading Speech AI models for accurate speech-to-text, speaker detection, sentiment analysis, chapter detection, PII redaction, and more. Join 5,000+ industry-leading companies—including Fireflies.ai, Glean, and Loop—unlocking the power of voice data and launching best-in-class products and experiences.

This is the 6th launch from AssemblyAI. View more

Universal-Streaming

Ultra-fast, ultra-accurate streaming STT for voice agents.

Universal-Streaming delivers all the streaming speech-to-text voice agents need in one robust API: ultra-fast immutable transcripts, higher accuracy, built-in endpointing, and transparent pricing at $0.15/hour with unlimited concurrency.

Free

Launch tags:

API•Developer Tools•Artificial Intelligence

Launch Team

Devon Malloy

AssemblyAI

Maker

📌

Six months ago, we launched Universal-2 to tackle last-mile accuracy in speech recognition—today, we’re excited to introduce Universal-Streaming, our purpose-built, real-time speech-to-text model designed specifically for voice agents. Universal-Streaming isn’t just fast—it’s a game-changer for real-time apps: ⚡ ~300ms immutable transcripts with no partial/final tradeoff 🧠 Intelligent endpointing that smooths out awkward pauses and interruptions 🔒 Accurate on the tokens that matter—emails, codes, names 🌎 Unlimited concurrency at just $0.15/hr with no surprise fees And it’s not just about the benchmarks—developers building real-world voice agents are already seeing the difference: more natural interactions, higher task completion, and easier scaling from 5 to 50,000+ concurrent users. Whether you're shipping AI assistants, realtime transcription tools, or something entirely new—Universal-Streaming gives you the power to build voice products your users will actually love to talk to. We can’t wait to see what you build—try it out and tell us what you think!

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2mo ago

Alex Redfern

LanguaTalk

@devon_malloy congrats on the launch. Couple of Qs: 1) which languages does it support? 2) do you have benchmark data by language vs 11labs Scribe and Deepgram Nova-3? Couldn't find answers to either.

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2mo ago

Meredith Rauch

AssemblyAI

@alex_redfern The Universal-Streaming model is currently available in english. As for the benchmark data, we have a robust breakdown on the comparison for Nova-3. A few impacts worth noting is the 44% increase in P50 Latency, 66% reduction in cost, and 21% better WER for alphanumerics. I will pass on the feedback for a Scribe benchmark. Thanks!

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1mo ago

Eric Wu

Pokecut

🚀 AssemblyAI is a total game-changer for anyone building AI products with voice data! Their speech-to-text accuracy is seriously impressive, and the extra features like speaker detection, sentiment analysis, and chapter detection make it super powerful. 🗣️✨

I especially love the PII redaction—privacy is a huge concern, and AssemblyAI handles it seamlessly. Knowing top companies like Fireflies.ai and Glean trust this platform gives me a lot of confidence, too! 💪

If you’re looking to unlock the true potential of voice data for your product, AssemblyAI is a must-try. Excited to see how it keeps evolving! 🔥

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2mo ago

Marat Zainullin

Hey, AssemblyAI Team,
I’ve been working on a fully offline, on-device streaming ASR engine for iOS.
Would love to get feedback or benchmark ideas!

If anyone's curious to try it on their device, I’m happy to add you to TestFlight — just DM me.
https://github.com/make1986/ios-streaming-asr-offline

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2mo ago

Deepgram Voice Agent API — Build production-ready voice agents with a unified speech-to-speech API.

Build production-ready voice agents with a unified speech-to-speech API.

Promoted

AssemblyAI Launches

Universal-Streaming Ultra-fast, ultra-accurate streaming STT for voice agents.

Launched on June 3rd, 2025

Universal 2 Speech-to-text for conversational data

Launched on October 31st, 2024

Universal-1 Multilingual speech AI model trained on 12.5M hours of data

Launched on May 21st, 2024

View all AssemblyAI launches

Do you use AssemblyAI?

4.8

Based on 32 reviews

Review AssemblyAI?

AssemblyAI is highly praised for its accurate and easy-to-integrate speech recognition API. Makers from Vercel and Tella commend its transcription capabilities, enhancing their products' functionalities. Me.bot highlights its support for various media types and ease of use. Users appreciate the API's speed, accuracy, and comprehensive documentation. While most feedback is positive, a few users noted minor issues with payment processes. Overall, AssemblyAI is a reliable choice for speech-to-text solutions.

+29

Summarized with AI

Pros

accurate transcription (11)

easy integration (8)

transcription API (7)

fast performance (4)

sentiment analysis (4)

excellent documentation (3)

content moderation (2)

multilingual support (2)

real-time transcription (2)

speaker diarization (2)

Pros

Cons

Reviews

All Reviews

Helpful

Xbei lu

•2 reviews

The precision was impressive, yet it was the comprehensive documentation and distinctive features such as Auto Chapters and Sentiment Analysis that truly swayed us.

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8mo ago

JD Prater

AssemblyAI

Fantastic! Thank you for the thoughtful feedback! It’s great to see these elements making an impact!

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7mo ago

Felix Tao

used AssemblyAI to build Me.bot

Me.bot

(2,335 points)

AssemblyAI offers an advanced, easy-to-integrate speech recognition API that excels in transcribing audio data accurately. It supports a range of media types! Super handy to use.

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1yr ago