How accurate are Line 21's AI captions?

Line 21 uses context-aware AI and a proprietary Intelligent Proofreader to target up to 99.99% accuracy by correcting ASR errors in real-time.

Does Line 21 work with Zoom?

Yes, Line 21 has a dedicated Zoom App Marketplace integration that delivers captions directly within the meeting interface.

Can I use Line 21 for live broadcasts on YouTube or Facebook?

Yes, it supports RTMP integration, allowing you to encode and stream captions directly to major social platforms and custom video infrastructures.

How many languages are supported for translation?

The platform supports automatic translation for over 100 languages, making it suitable for international conferences and global events.

What is the difference between ASR and Human Live Captions on Line 21?

ASR (Automated Speech Recognition) is fast and cost-effective for everyday meetings, while Human Live Captions use accredited professionals for high-stakes verbatim requirements like legal proceedings.

What are ASR Glossaries?

Glossaries are custom word lists used to train the AI on specific terms, names, or technical jargon to ensure they are transcribed correctly during a live session.

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Live captions

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Line 21

AI-powered real-time captions and translations for live events and video. Features an intelligent proofreader, supports 100+ languages, and integrates with Zoom, Teams, and RTMP streams.

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Rating

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Upvotes

3 months ago

Listed

Live captions

Real-time translation

Accessibility

Video conferencing

RTMP streaming

Multilingual

ASR

Event technology

Webinar tools

Tool information

Provider

L21 Limited

Platforms

Web

Zoom

Microsoft Teams

Windows

macOS

Languages

English

Spanish

French

Portuguese

German

Hindi

Croatian

Thai

Japanese

Chinese

Over 100 languages supported

Added to directory

3 months ago

Last updated

about 1 month ago

Rating

Not available

Pricing

Contact

About Line 21

What the tool does and who it's for

Line 21 is an AI-assisted live captioning and translation platform designed for global events, broadcasts, and corporate meetings. It combines advanced Automatic Speech Recognition (ASR) with a proprietary "Intelligent Proofreader" that corrects transcriptions in real-time to ensure maximum accuracy. The platform supports over 100 languages for live translation and offers seamless integration with major video conferencing tools like Zoom and Microsoft Teams, as well as RTMP-based streaming setups for social media and custom infrastructure. In addition to AI-driven automation, Line 21 provides professional human captioning services for high-stakes environments, making it a comprehensive accessibility solution for multilingual audiences.

Key capabilities

Intelligent AI Proofreader: Automatically corrects errors in real-time to maintain high transcription accuracy.

Multilingual Live Translation: Instantly translates spoken words into over 100 different languages for global audiences.

Seamless Platform Integration: Native apps for Zoom and Microsoft Teams, plus support for YouTube and Facebook Live.

RTMP Encoding: Directly encode CEA-608/708 captions into video feeds and RTMP streams for professional broadcasting.

Hybrid Captioning: Flexibility to switch between high-speed AI-generated ASR and verbatim human captioning.

Custom ASR Engines: Utilizes hand-picked language engines specifically optimized for nuanced dialects and technical terminology.

Second Screen Support: Ability to send live text to external displays or specialized accessibility devices.

Context-Aware Glossaries: Supports custom vocabularies to improve accuracy for niche industry jargon and names.

Pricing

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