Captions Adjustable
Group: images-and-media • Guideline: captions
Summary in Plain English
Caption appearance can be adapted - font size, weight, style and colour, background colour and transparency, and where they sit on screen - along with any associated visual indicators.
Why It Matters
Fixed captions are unreadable for many low-vision viewers. Size, contrast and position are the settings that make the difference between legible and not.
Test Procedure from the W3C Draft
Quoted from the provision's informative document, informative/guidelines/images-and-media/captions/captions-adjustable.md. It is the group's own procedure, not an editorial testing guide.
Procedure
For each caption:
- Check that the appearance of captions and associated visual indicators is adaptable including font size, font weight, font style, font color, background color, background transparency, and placement.
Expected results
- #1 is true.
W3C Working Group Status
The draft records no open editors' notes on this provision.
W3C Threads on This Provision
3 GitHub threads carrying 13 comments, fetched from w3c/wcag3 by the tracker. Titles, numbers and states are the threads' own.
What the Argument Is About
Whether WCAG 3 should prescribe how captions actually render, and whether closed captions should be preferred over open captions precisely because only closed captions can be adjusted.
Positions taken in the thread
WCAG recommends captions but specifies nothing about whether the result is readable or usable. Proposes WCAG 3 adopt the Association of National Advertisers captioning standards, which are the basis for the FCC's television captioning rules and the National Park Service captioning guidelines. Filed as #119 in October 2024 and has drawn no reply from anyone in the thread.
PoornimaSubramanian's case in #234 is that closed captions give the user control over when to turn them on or off, and can be customised by the editor for font face, size and position, so a rating should turn on the presence and accuracy of closed captioning, with a Rating 0 for informational or essential video carrying no metadata. WilcoFiers's opening question in #23 pushes further, asking whether open captions should be disallowed on new video material at all, and noting closed captions may be routable to a braille display. Neither has been answered in the threads.
Open captions are part of the time-based media, so they need no alternative text of their own; the alternative required at Level A is for the video. The video would fail 1.1.1 only if there were no text alternative identifying the video itself, and a transcript for audio information is not required until 1.2.8. Also corrects the video-only framing: captions are equivalents for audio, so video-only content has on-screen text, not captions.
Opened by arguing open captions are literally images of text and so fail 1.4.5 at AA, or 1.1.1 at A if they lack alt text, since video frames have no alt text mechanism. Conceded awkawk's reading but held the underlying proposal: because captions are explicitly an alternative for audio, WCAG 3 should require open-captioned video to also have a text transcript. Raised as an edge case open-captioned instructional video whose only audio is royalty-free music, where the captioned information is effectively video-only time-based media.
mraccess77 argues exemptions are a regulator's job, since inaccessible video causes clear discrimination in areas such as fair housing and healthcare, and cites the shift on audio description for entertainment as precedent that entertainment is a right too. mitchellevan agrees on same weight, on the grounds that user needs and technical feasibility are the same, that "promotional" is hard to define, and that regulations such as the US Air Carrier Access Act already exempt advertising. Nobody argued the other side.
Agreed
- Open captions do not need their own alternative text, because they are part of the time-based media — awkawk's correction, which u9000-Nine accepted directly.
- Whether advertising and promotional video is exempt is a matter for regulators rather than the technical standard; the point drew no rebuttal.
- The reasons given for favouring closed captions — user control over turning them on or off (PoornimaSubramanian), and WilcoFiers's question noting they may be customisable to a user's preferences and routable to braille — went unchallenged. Nobody argued the reverse case for open captions.
Still open
- Whether open captions should be restricted or prohibited on new video material — WilcoFiers's question in #23, unanswered.
- Whether WCAG 3 should import an external caption presentation standard — JLS2024's #119 is still without a single response.
- How caption accuracy is graded. WilcoFiers asks how to weigh missing or wrong words, missing audio cues, missing speaker identification and missing punctuation needed to convey emphasis, sentence ends or sarcasm; no one has proposed a scheme.
- Whether a rating keyed to the presence and accuracy of closed captions, as PoornimaSubramanian proposes, is workable as a conformance model.
- u9000-Nine's edge case of open captions over a music-only audio track, which awkawk asked about and which was not resolved.
Note
Two of this provision's three threads, #119 and #234, are issue bodies with no replies at all; #234 has been open since January 2022. Every recorded comment here comes from #23, which is shared with the two speaker-identification provisions.
- #23 Create Audio and video alternatives guideline open 13 comments · updated 2026-09-11
- #119 Can WCAG add caption standards, so that captions are readable, usable and benefit the people they are intended to assist? open 0 comments · updated 2026-04-02
- #234 WCAG 3.0 Draft Guideline Captions open 0 comments · updated 2026-05-01
WCAG 2.2 Criteria That Map Here
From this site's reviewed WCAG 2.2 → WCAG 3 map. The map is an interpretation, not a W3C mapping: W3C has not published one yet.
No mapping recorded. No WCAG 2.2 criterion in this site's map is recorded as a predecessor of this provision.
W3C Raw Source Text
Verbatim from guidelines/groups/images-and-media/captions/captions-adjustable.md · informative document: informative/guidelines/images-and-media/captions/captions-adjustable.md
The appearance of captions, including associated visual indicators, is adaptable including font size, font weight, font style, font color, background color, background transparency, and placement.