1.2.4 Captions (Live)
Live videos with sound, such as webinars or live streams, need real-time captions.
Level AAPrinciple 1: Perceivable
What does it mean?
When you stream live audio together with video, for example a webinar, an online event or a live product launch, you need to provide captions in real time. These are usually produced by a professional live captioner or a carefully supervised captioning service.
This applies to synchronised media, meaning video with sound. Live audio without video is not covered by this criterion. Once a live stream is recorded and published, the rules for pre-recorded media apply.
Who does it help?
- Deaf and hard-of-hearing people
- People following an event without sound
- People who follow spoken language better with text support
Common failures
- A public webinar or live stream with no captions at all
- Live captions that are so delayed or inaccurate that the content cannot be followed
- A recording of the live event published later without corrected captions
How we test it
- evidence Evidence: our scanner collects material such as screenshots, lists and measurements.
Test question: Live audio content (streams) needs live captions.
A person decides every criterion. No criterion ever passes automatically.
How to fix it
<!-- Live stream embedded, captions not enabled -->
<iframe src="https://stream.example.com/live/123" title="Live event"></iframe><iframe src="https://stream.example.com/live/123?captions=on"
title="Live event with live captions"></iframe>
<p>Live captions are on by default. You can turn them off in the player.</p>The player is configured with live captions enabled and the page tells viewers they are available.
Practical tips
- Book live captioning when you plan the event, not on the day.
- Check that your streaming platform can display live captions before you choose it.
Guides and patterns on this
Official source
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