Pricing
Not listed
Official monthly price not confirmed
- API
- Documentation and API overlays are listed among Line 21 caption delivery features.
Line 21
● Identity checkedVideo · Vendor site 2026-10-04
Line 21 is a UK-based live captioning platform for streaming, in-venue, and broadcast events with human captioners, ASR, AI proofreading, translations, and multi-destination output. It integrates with YouTube, Twitch, Teams, Zoom, RTMP, and HLS workflows for 100+ languages.
- Category
- Video
- Free access
- Not confirmed
- API access
- Documentation and API overlays are listed among Line 21 caption delivery features.
Is Line 21 right for you?
A good fit for
Event producers, broadcasters, and accessibility teams needing accurate multilingual live captions across venues and streams.
Before you choose
Public pricing is usage-based per hour or minute for caption services rather than fixed monthly USD software tiers.
Intelligent live captions
Line 21 combines human captioning, ASR, AI proofreading, and translations so live events stay accessible across streams, venues, and broadcast chains.
What it can do
Features & capabilities
Unknown is different from unavailable. Each fact carries its own evidence.
| Capability | Value | Evidence | Checked |
|---|---|---|---|
| AI proofreader | Line 21 advertises a context-aware AI proofreader that fixes live caption errors before audiences see them. | Facts sourced | 2026-10-04 |
| Language coverage | Marketing states support for more than 100 languages via human captioning, ASR, and translation. | Facts sourced | 2026-10-04 |
| Streaming outputs | Platform supports RTMP, HLS, embeddable players, and integrations like YouTube, Twitch, Teams, and Zoom. | Facts sourced | 2026-10-04 |
Understand the total cost
Line 21 pricing & plans
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Frequently asked questions
What is Line 21 used for?
Line 21 is a UK-based live captioning platform for streaming, in-venue, and broadcast events with human captioners, ASR, AI proofreading, translations, and multi-destination output. It integrates with YouTube, Twitch, Teams, Zoom, RTMP, and HLS workflows for 100+ languages.
Does Line 21 have a free plan?
Not confirmed. This record does not confirm an ongoing free plan.
How much does Line 21 cost?
A listed monthly price has not been confirmed. See the plan cards for entitlements, billing commitments and seat minimums.
Can I use Line 21 through an API?
Documentation and API overlays are listed among Line 21 caption delivery features.. API access and subscription access may have different terms; consult the linked sources.
What should I check before choosing it?
Public pricing is usage-based per hour or minute for caption services rather than fixed monthly USD software tiers.
Price history
No retained pricing changes yet. A current price alone does not establish a historical trend.
How this profile is supported
Identity and profile
Reviewed vendor source
Read original source ↗Facts apply to the named version and check date. Send a sourced correction if something changed.