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Features

Automatic Language Detection

Build powerful multilingual speech applications. Detect the dominant language in any audio file and transcribe it with industry-leading accuracy across 99 languages, from one API.

Detect the spoken language with less than 10 lines of code

Enable Automatic Language Detection in your transcription request, and automatically detect and transcribe 99 languages in your audio files, with no language tags or manual routing required.

One API, 99 languages

Detect the dominant language and route every file to the best available speech model for it, with industry-leading accuracy across 99 languages.

Industry-leading accuracy

Reduce transcription errors on multilingual audio and improve the performance of your products with the most accurate language detection available.

Control the detection

Restrict detection to a list of expected languages and set a fallback, so an unexpected detection never derails a transcription.

Use cases

Transcribe global content without language barriers

Serve every market from a single integration, with no manual language selection required.

Automate multilingual call centers

Subtitle global video content

Document international meetings

Simplify multilingual podcasts

Power multilingual voice assistants

Expand your product globally

Route content by language

Index multilingual archives

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