WCAG 1.2.1 Audio-only and Video-only (Prerecorded)

What it asks

This rule covers two kinds of recorded media that have only one channel. Audio-only content, such as a podcast episode, an interview recording or a voice message, needs a text alternative that carries the same information: who said what, and any meaningful sounds. Video-only content, such as an animation with no soundtrack or a silent screen recording, needs either a text alternative that describes what happens or an audio track that narrates it.

The alternative has to be equivalent. A transcript of a podcast that skips a speaker, or a sentence saying "a demo of the new dashboard" standing in for a two-minute silent video, does not do the job. The reader should come away knowing what a listener or viewer would know.

There is one exception. If the media is itself an alternative for text, for example an audio version of an article that is clearly labelled as such, it does not need another alternative. The text it stands in for is the alternative.

Media with both sound and pictures is not covered here. That is synchronised media, and it falls under 1.2.2 Captions (Prerecorded), 1.2.3 and 1.2.5.

Its official name is success criterion 1.2.1 Audio-only and Video-only (Prerecorded), at Level A. It was added in WCAG 2.2, under guideline 1.2 Time-based Media and the principle Perceivable. The W3C’s normative text says, in part:

“An alternative for time-based media is provided that presents equivalent information for prerecorded audio-only content.”

From WCAG 2.2, W3C. Full explanation: Understanding 1.2.1 Audio-only and Video-only (Prerecorded).

Who it helps

Deaf and hard of hearing people, who cannot hear a podcast and need to read it instead. People who are blind, who cannot see a silent video and need it described. Deaf-blind people, who rely on a transcript read through braille.

It also helps anyone in a quiet office or on a noisy train, anyone whose first language is not the one spoken, and anyone who would rather skim a transcript than listen to an hour of audio.

What passes and what fails

These pass

• A podcast page with a full transcript below the player, naming each speaker.
• A silent product demo with a paragraph under it describing each step shown.
• A silent animation with a narration track that can be switched on.
• An audio recording of an article, labelled "Listen to this article", on the page with the article itself.
• A short silent video of a logo animation that carries no information, with a text label saying what it is.

These fail

• A podcast episode page with only a title, a date and a player.
• A silent product demo loop on a home page, showing the product in use, with no description anywhere.
• An auto-generated transcript that runs everything together and leaves out who is speaking.
• A voicemail-style audio message in a support flow with no text version.
• A transcript on a different page, with no link from the audio to it.

How to test it by hand

1. Find every piece of recorded media on the page: audio players, embedded podcast widgets, video elements, animated content and third-party embeds.
2. For each, play it and note whether it has sound, pictures, or both. Only the one-channel ones are covered here.
3. For audio-only, look for a transcript on the page or clearly linked from it. Read it against the recording. Does it name the speakers and include meaningful sounds?
4. For video-only, look for a text description or a narration track. Watch the video and check that the description covers what it shows.
5. Check whether the media is labelled as an alternative for text that is already on the page. If so, it is exempt.
6. Note each recording with no alternative, or with one that leaves out information.

What automated testing can decide

What a machine can decide

Automated testing can find the media. Audio and video players are in the page, and a tool can list them and note whether a text track or a transcript link sits beside each one. Looking and finding nothing is also what makes a Not Applicable answer defensible: an audit that searched for media and found none has positive evidence.

What it cannot

Automated testing cannot tell from a page whether a video has a soundtrack or whether an audio file contains speech. It cannot know whether a link called "Transcript" leads to a transcript of this recording. And it cannot judge whether a transcript is complete without listening to the recording and reading the text side by side.

How Dreven handles it

Dreven finds the audio-only and video-only recordings on your pages and shows you each one, with any transcript or description found alongside it. Where a page has no such media, the report says the page was checked and none was found, which is the evidence behind a Not Applicable result.

A reviewer listens or watches, decides each result, and the report records what was decided and why.

No automated check makes a site conform. In Dreven, a person reviews the results and signs the report.

Related criteria

• 1.2.2 Captions (Prerecorded) (Level A). Video with sound needs captions.
• 1.2.3 Audio Description or Media Alternative (Prerecorded) (Level A). Video with sound needs a spoken description or a full text alternative.
• 1.1.1 Non-text Content (Level A). Still images need text alternatives in the same spirit.
• 1.4.2 Audio Control (Level A). Audio that starts on its own must be easy to stop.

Questions people ask

All WCAG 2.2 criteria, in plain words