MCP简体中文Upgrade
Market/Categories/Video Generation & Editing/Line 21

Independent product intelligence · Worldwide · 2026-05-01 → 2026-07-31

Line 21line-21.com

Line 21 provides dynamic captioning and translation solutions, leveraging AI and human expertise to deliver accessible content worldwide.

Video Generation & Editingline-21.comTracked since 2026-08-211 discovery source
1KBacklinks
128Referring domains
21Domain authority
-4.6%Referring domains · 90 days

Authority & distribution

How strong is Line 21’s web footprint?

Backlinks measure accumulated distribution; referring domains show how broadly that authority is spread. Both are observable on the open web, so both are published for every product here.

Backlinks

1KCurrent snapshot

Referring domains

128Current snapshot

Authority

21Domain authority · category median 22

90-day move

-4.6%Referring domains, last 90 days
At 21, Line 21 sits below the 22 median for its category.

Trajectory · Pro

The counts above are the latest of 370 daily observations. The curve through them is on the full profile.

See the trajectoryOpen the full profile

AI referral visibility

Which AI assistants are already sending Line 21 traffic?

Measured · Pro

Measured for this product: AI referral traffic.

Unlock this profileOpen the full profile

Product profile

What Line 21 is selling.

Traffic makes more sense when you can connect it to the actual product promise.

“Line 21”

Line 21 provides dynamic captioning and translation solutions, leveraging AI and human expertise to deliver accessible content worldwide.

Video Generation & EditingSeen 2026-08-21 → 2026-08-21Coverage tier C

What we have measured

4 of 8 signal groups are available for this product: identity, authority and backlinks, AI referrals, search demand.

Not measured for this domain: traffic and engagement, audience demographics, country distribution, acquisition mix. Those sections are left out of the page rather than filled with estimates.

Canonical website: https://line-21.com

Observed across 1 discovery source.

Research questions

What the evidence answers about Line 21.

Every answer is tied to a source we collected, and the questions with no evidence behind them are left unanswered rather than guessed.

What does Line 21 do and what problem does it solve?

Line 21 provides AI-powered live captioning and translation services to make audio and video content accessible. It combines AI with human expertise to deliver accurate, real-time captions for various media formats and live events.

What features or services does Line 21 offer?

Line 21 offers a suite of features including manual captioning, ASR, AI translations, an AI proofreader, an embeddable player, and a meeting bot. It supports RTMP and HLS streaming, caption encoding (CEA 608/708), and provides an API for integration.

Which platforms and streaming services does Line 21 integrate with?

Line 21 integrates with over 15 platforms and streaming services, including YouTube, Twitch, Facebook, Vimeo, Microsoft Teams, Zoom, and custom RTMP/HLS streams.

What is Line 21 used for and in what situations?

Line 21 is used to add intelligent live captions to events like online streaming, in-venue presentations, and broadcasts. It supports over 100 languages and integrates with platforms such as YouTube, Twitch, and Microsoft Teams.

Who is Line 21 designed for?

Line 21 is designed for content creators, broadcasters, event organizers, and businesses that need to provide accessible, multilingual content to a global audience, whether for live events or on-demand video.

What is Line 21?

Line 21 is a live captioning and translation service that uses AI and human expertise to deliver accessible content for live events and video streams across more than 100 languages.

Behind the lock

Unlock full Line 21 intelligence.

  • Backlink trajectoryThe figures above are the latest observation. The daily curve behind them holds 370.
  • AI referral detailHow much traffic assistants send.
  • Search structure and ranking depthOrganic against paid, brand against non-brand, and how many keywords rank in the top three against the long tail — which is what decides whether the demand is portable or tied to the name.
  • The rest of the marketPage through every leaderboard 100 rows at a time, put any five products side by side, and query the whole dataset over API / MCP.

Worldwide estimates · Data period 2026-05-01 → 2026-07-31. Figures are measured estimates intended for market research. Signals we have not measured for this domain are omitted, never estimated; a measured zero is still reported as zero. How this was measured