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Features

Key Phrases

Find what a recording is really about. Extract its most significant words and phrases, each with a relevance rank, how often it was said, and exactly where.

Extract key phrases with less than 10 lines of code

Enable Key Phrases in your transcription request and receive a ranked list of the concepts and highlights in the audio, returned separately from the transcript text.

Ranked by relevance

Every phrase comes back with a relevancy rank and an occurrence count, so you can surface the handful that matter instead of a word cloud.

Timestamped to the audio

Each phrase carries the timestamps where it was spoken, ready for search, highlight reels, and clip generation.

Pairs with topics and summaries

Combine Key Phrases with Topic Detection and Summarization to describe a recording from three angles in one request.

Use cases

Make every recording searchable

Give hours of audio the handful of phrases that describe them.

Index a media library by concept

Auto-tag recordings at upload

Find clip-worthy moments

Generate show notes

Spot emerging themes across calls

Highlight key concepts in lectures

See what customers keep asking about

Enrich analytics with phrase-level signal

Join 200K+ developers building new experiences with voice data

If you have an hour of content, the difference between 99% accuracy and 97% accuracy, it's a lot of time for that person to review. So you could cut down their workflow from taking half an hour, to 20 minutes, to 15 minutes — it's huge, right?

Joshua Grossberg

Joshua Grossberg

CTO, Kapwing

Investments in STT improvements always pay for themselves, since it is such a critical building block of the voice pipeline.

Lindsay Liu

Lindsay Liu

Co-Founder & CEO, Super

AssemblyAI's managed API endpoint and diarization won me over — something Whisper couldn't provide.

Josh Mohrer

Josh Mohrer

Founder, Wave.co

We needed a provider that could scale with us — offering unlimited concurrent streams, fair pricing, and responsive support.

Mark Barbir

Mark Barbir

CEO, Earmark

The transcription accuracy, reliability, and speed of AssemblyAI's API have greatly enhanced our operations.

Raj Shankar

Raj Shankar

SVP Product, Calabrio

Our free to paid conversion rate doubled after implementing AssemblyAI.

Colin Treseler

Colin Treseler

Founder & CEO, Supernormal

The accuracy was strong, but the great documentation and unique models like Auto Chapters and Sentiment Analysis is what really won us over.

Nathan Webb

Nathan Webb

Product Manager, Aloware

Calls are and will remain a pertinent part of the customer service journey. Customer service isn't moving entirely to chatbots or chat interactions.

Dr. Shane Lynn

Dr. Shane Lynn

CEO, EdgeTier