Line 21

Paid

Comprehensive real-time captioning solutions for all your accessibility needs.

#captions#accessibility#AI captioning#human captioning#live captioning#proofreading#translations#automatic speech recognition#technical support#live events#education#corporate use#broadcasting#notetaking#government schemes

Inputs: audio, video

Starting Price

$0.04/mo

Type

Saas

Company

L21 Limited

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About Line 21

Line 21 is a complete and highly flexible live captioning platform that supports both human and AI-powered solutions. It allows users to integrate accurate closed captions into live events—whether online streaming, in-venue, or broadcast. The platform offers a wide range of services including manual captioning, automatic speech recognition (ASR), AI Proofreader, AI translations in 120+ languages, RTMP/HLS streaming, caption encoding (CEA 608/708), embeddable player, meeting bot, and API access. Trusted by agencies and event organizers, it provides a modern software stack with 15+ integrations (YouTube, Twitch, Facebook, Vimeo, Zoom, Microsoft Teams, etc.) and 10+ AI models. Pay-as-you-go pricing with no plans means users only pay for minutes used, with per-hour rates for specific services.

Key Features

Human and AI-powered captioning

Live support during events

AI Proofreader for context-aware error correction

AI Translations in 120 languages

Automatic Speech Recognition with high accuracy

Global network of professional captioners

Low latency video caption encoding

Transcripts available in multiple formats

Technical support for setup and integration

Accessibility in over 100 languages

Pros & Cons

Pros

Supports both human and AI captioning, allowing flexibility for accuracy vs. speed
Wide language coverage with over 100 languages and 120+ for AI translations
AI Proofreader with context-aware correction reduces errors in real-time
Pay-as-you-go pricing with no plans or long-term commitments
15+ integrations with major streaming platforms and meeting tools
Low-latency streaming and encoding (RTMP, HLS, CEA 608/708)
Technical support available live during events
Global network of professional captioners for high-accuracy needs

Cons

Pricing per minute can add up for long or frequent events
Dependence on internet connectivity for real-time captioning
AI accuracy may vary with strong accents or poor audio quality
Human captioner rates ($120/hr) may be expensive for budget-constrained users

Best For

Event Organizers: Ensure accessibility for all audience members by providing real-time captions during live events.Educational Institutions: Facilitate inclusive learning by offering real-time, multilingual captions for virtual and in-person classes.Broadcast Networks: Deliver accurate and timely captions for live broadcasts, including news and sports events.Corporations: Enhance corporate communication with real-time captions during meetings and conferences, ensuring inclusivity and compliance.Captioning Agencies: Leverage advanced AI and human captioning for a variety of client needs, across different languages and specializations.Deaf or Hard of Hearing Individuals: Access real-time captions for better engagement in live events, educational settings, and workplace meetings.Government Programs: Support accessibility initiatives such as the UK's Access to Work scheme with reliable real-time captioning.Technical Teams: Receive dedicated support and consultation for setting up and managing captioning integrations and deliveries.Concert Organizers: Provide captions for lyrics and dialogues, making performances accessible to all attendees.Students: Benefit from electronic notetaking for a condensed version of lectures, enhancing study and review sessions.

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