Line 21: Reviews, Features, Pricing, Alternatives

Line 21

paid

Automate live captioning across 100 languages.

25 monthly visits

Real-time Translation

official socials:

line 21 website

Line 21 is a UK-based live captioning service that provides both human and AI-powered captioning for live events. It supports over 100 languages and integrates with major streaming platforms such as YouTube, Twitch, Facebook, Vimeo, and conferencing tools like Zoom and Microsoft Teams. Key features include automatic speech recognition (ASR), real-time AI proofreading, AI translations, and support for RTMP and HLS streaming. The platform is designed for events ranging from keynotes and festivals to corporate meetings and webinars, offering flexible output options including embedded players, CEA 608/708 captions, and custom overlays.

Key Benefits

Supports both human and AI captioning
AI Proofreader for real-time corrections
100+ languages supported
Integrates with major streaming platforms

starting price

$0.12 / hour/ usage-based(hls video streaming)

tags

Transcription Accessibility Real-time Translation

integrations

youtubetwitchfacebookvimeocustom rtmpmicrosoft teams

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Line 21 Analytics

Traffic, engagement & audience insights

Traffic Trend

Jul 2025 - Jun 2026

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Top Keywords

SEO Keyword	Volume	CPC
1line 21 closed captioning	450	-
221 over subs	10	-

Analytics data is estimated (from third-party analytics providers) and for reference only.

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