It’s no secret: I like the Web Content Accessibility Guidelines. Not only do they give us the four base principles of accessibility (perceivable, operable, understandable, and robust), but they also have neat guidelines and checkpoints to test for. We call each checkpoint a “success criterion.”

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I'm a web accessibility professional who cares deeply about inclusion and an open web for everyone. I work with Axess Lab as an accessibility specialist. Previously, I worked with Knowbility, the World Wide Web Consortium, and Aktion Mensch. In this blog I publish my own thoughts and research about the web industry.

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There are several reasons why WCAG 2 is such a long-living standard. The main reasons, in my opinion, are the very solid foundation it is built on, the accumulation of experience with the standard in practice, and the modest attempts at modernization. While not perfect, WCAG 2.1 and 2.2 added important aspects for accessibility.

But some aspects of WCAG have also been created under the premise of a 2005-era web that do not hold true for 2025. I think one of these aspects is visible in this recent discussion about audio descriptions. The discussion is about the requirements for audio description in media that has no pauses to insert the audio description in. In particular this is about SC 1.2.5 Audio Description (Pre-Recorded):

1.2.5 Audio Description (Prerecorded) (Understanding)

(Level A)

Audio description is provided for all prerecorded video content in synchronized media.

While one would think that this would require audio descriptions to be present in all videos, apparently the people who wrote the success criterion 20 years ago always meant to exempt videos where there is no space for audio description.¹

Even if that was always the intention and the Working Group understood this at the time, the whole context of online videos was different. YouTube was released in 2005. Video on the internet looked completely different. Either it was full-scale movies or news reports. Shorts and TikToks weren’t even thought of. Videos were either big-budget productions or hobby projects. And you would always find space in the bigger projects. For smaller outfits, adding audio descriptions to videos was quite difficult without cutting and re-editing the videos. And we used Flash as video players.

But this is not how 2025’s internet works. You have very succinct videos that contain visual information and audio information, but there will be no good gap to insert the audio description. The solution, however, is also quite simple today: add the audio description before or after the video. You can even pause the video in the middle and play an audio file if you like² . HTML <audio> and <video> elements make this pretty straightforward. You can even use the speech API and generate the audio description in the browser.³

Without audio descriptions, videos cannot be perceived by people who are blind or visually impaired. WCAG is best when it sticks to its principles. If the Working Group decides to amend the success criterion, I’ll of course judge it that way, with a note that it doesn’t agree with WCAG’s principle. I could be swayed if the result was that WCAG would require a written alternative instead. But as the current argument is that you have audio description by default if there is not enough space, SC 1.2.3 Audio Description or Media Alternative (Prerecorded) must be met under those circumstances:

1.2.3 Audio Description or Media Alternative (Prerecorded) (Understanding)

(Level A)

An alternative for time-based media or audio description of the prerecordedvideo content is provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

This is clearly a loophole or at least too loosely defined. If the intention was to allow no audio descriptions when there is not enough space but require a media alternative in these cases, then that should be clearly put into the SC’s text. And for what it’s worth, Making Audio and Video Media Accessible by WAI, says on its page about descriptions:

If all the descriptions do not fit in the spaces (as described in Space in audio above), you’ll need to develop a separate audio file and also edit the visual track. This requires skills and software for audio recording, audio editing, and video editing.

The resource is really good, and I recommend reading through it.

What to do?

For most testers, I would keep the requirement for audio descriptions. Even if it was clear for WCAG back in the day, not having audio descriptions is actively locking out your users, and it might even be a legal liability. The best advice you can give is to integrate descriptions in the main audio of the video. Instead of saying “These are the new ACME sneakers”, you say, “These are the new white ACME sneakers with blue application of our logo on the outside.”

This also shows one of the main advantages of planning for accessibility. If you do it planned from the beginning, you don’t even need to read a single WCAG SC to ensure your stuff is accessible.