WCAG 1.2.1: Audio-only and Video-only (Prerecorded)
A deaf user cannot hear a podcast, and a blind user cannot see a silent animation. This criterion asks that prerecorded media which is only audio or only video has a text alternative — or, for silent video, an audio track — that presents the equivalent information. Get this one right and podcasts, recorded talks, silent demos, and time-lapses reach the people who cannot use one of their two channels.
The success criterion, in full
For prerecorded audio-only and prerecorded video-only media, the following are true, except when the audio or video is a media alternative for text and is clearly labeled as such: Prerecorded Audio-only: An alternative for time-based media is provided that presents equivalent information for prerecorded audio-only content. Prerecorded Video-only: Either an alternative for time-based media or an audio track is provided that presents equivalent information for prerecorded video-only content.
In plain terms: audio-only needs a transcript; video-only needs a text description or an audio track. The single exception is media that merely re-presents text already on the page and is clearly labeled as such — that text is already the alternative.
Who this helps
A text alternative turns a single-channel recording into content everyone can reach — it can be read, searched, translated, and read aloud by assistive technology:
Deaf and hard-of-hearing users
Cannot hear audio-only content at all. A transcript is the only way they can access a podcast, interview, or recorded announcement.
Blind and low-vision users
Cannot see video-only content. A text description or audio track is what conveys the visual information in a silent animation or demo.
People with cognitive and learning disabilities
May process written text more easily than fast speech or motion, and can use text-to-speech and reading tools on a transcript.
Users in sound-sensitive environments
In a library, an office, or on public transport without headphones, a transcript lets people read content they cannot play out loud.
Users on limited bandwidth
When someone disables audio or video to save data, the text alternative keeps the information available in a lightweight form.
Non-native language speakers
Often understand written text better than spoken audio, and can run a transcript through translation tools at their own pace.
What the requirement covers
1.2.1 applies only to prerecorded media that carries information in a single channel — sound but no meaningful picture, or picture but no meaningful sound. The first practical step is to classify each media file, because audio-only and video-only need different alternatives:
- Audio-only content. Podcasts, interviews, recorded lectures, audiobooks, and audio announcements. Provide a complete transcript with speaker labels and descriptions of important sounds.
- Video-only content. Silent animations, time-lapse footage, screen recordings without narration, and visual demonstrations. Provide a text description of everything shown, or an audio track that narrates it.
- What a transcript must contain. All spoken words verbatim, speaker identification, and meaningful non-speech sounds ([applause], [music fades in]). It must be findable, keyboard accessible, and equivalent to the audio.
- What a video description must contain. Every visual element and action that conveys information, in logical sequence, specific enough that a blind user can follow the process — not a vague one-line summary.
The exception, briefly
The one carve-out is media that is itself a media alternative for text and is clearly labeled as such. If an audio recording simply reads an article that already appears in full on the page, the article is the text alternative and the recording needs nothing extra. Note that 1.2.1 stops at media that is only audio or only video — once a clip has both a soundtrack and moving pictures, you move on to the captions and audio-description criteria under the other 1.2.x guidelines.
Pass and fail examples
✓ Passes 1.2.1
- A podcast with a full transcript that identifies each speaker and notes the background music.
- A recorded lecture accompanied by a complete, structured text transcript on the same page.
- A silent keyboard-navigation animation with a step-by-step text description of every action shown.
- A time-lapse video paired with an audio track that narrates what is happening on screen.
- An audio version of an article, clearly labeled as such, sitting beside the full written article.
✗ Fails 1.2.1
- An audio-only company announcement published with no transcript at all.
- A podcast whose “transcript” omits speaker labels or the meaningful sounds in the recording.
- A silent installation video described only as “video shows the installation process.”
- A visual demonstration whose text alternative is too vague to let a blind user follow the steps.
- An audio recording of text that is not clearly labeled as an alternative and has no transcript.
Code examples
Audio-only: missing vs. linked transcript
An <audio> element on its own carries nothing for a deaf user. Pair it with a transcript that is visible or clearly linked on the page.
<!-- ✗ Audio-only content with no alternative -->
<audio controls src="episode-5.mp3"></audio>
<!-- ✓ Audio with a visible, structured transcript -->
<audio controls src="episode-5.mp3"></audio>
<section aria-label="Transcript of Episode 5">
<h2>Transcript</h2>
<p><strong>[Host]:</strong> Welcome to Web Accessibility Today.
I'm Sarah Johnson.</p>
<p><strong>[Guest]:</strong> And I'm Mike Chen from the
A11y Initiative.</p>
<p><em>[Background music fades in for 3 seconds]</em></p>
<p><strong>[Host]:</strong> Today we're discussing WCAG…</p>
</section>Video-only: text description or audio track
Silent video needs either a text alternative describing the visuals or an audio track that narrates them. A vague caption is not enough.
<!-- ✗ Silent video with a vague, non-equivalent blurb -->
<video src="keyboard-demo.mp4" muted controls></video>
<p>Video shows keyboard navigation.</p>
<!-- ✓ Silent video with a full text description nearby -->
<video src="keyboard-demo.mp4" muted controls
aria-describedby="kbd-desc"></video>
<section id="kbd-desc">
<h2>Description: keyboard navigation demo</h2>
<ol>
<li>User presses Tab; focus moves to the search button,
highlighted with a blue outline.</li>
<li>Tab again moves focus to the navigation menu.</li>
<li>Arrow keys step through Home, About, Services, Contact.</li>
<li>Enter on "Services" opens a submenu.</li>
</ol>
</section>Video-only: an audio description track
As an alternative to text, you can supply a narrated audio track for the silent video so the visuals are described as it plays.
<!-- ✓ Silent video with a descriptive audio track -->
<video controls>
<source src="timelapse.mp4" type="video/mp4">
<track kind="descriptions" src="timelapse-desc.vtt"
srclang="en" label="Audio description">
</video>
<!-- Or offer a separately narrated version of the clip -->
<a href="timelapse-described.mp4">
Watch the audio-described version
</a>Interactive demo
Toggle transcripts on and off to feel the difference between accessible and inaccessible media, then practice writing a transcript and watch the live feedback catch missing speaker labels and sound descriptions.
Toggle to simulate the experience of a deaf or hard-of-hearing user who relies on the text alternative instead of the audio.
Good example: podcast with a complete transcript
Why this passes
- • Full transcript with speaker identification.
- • Describes important non-speech sounds such as the music.
- • Findable, keyboard accessible, and read by assistive tech.
Failing example: audio with no transcript
Problems with this approach
- • No transcript for deaf or hard-of-hearing users.
- • Critical information is completely inaccessible.
- • Fails WCAG 1.2.1 at Level A.
Good example: silent animation with a detailed text alternative
Silent animation would play here
(Keyboard navigation demonstration — no audio)
Why this passes
- • Every visual action is described step by step.
- • Specific visual feedback (the blue outline) is captured.
- • A blind user gets the same information as a sighted viewer. An audio description track would satisfy the requirement too.
Practice writing a transcript
Draft a transcript for an audio clip. The live feedback below checks for speaker labels and descriptions of important sounds — the two things authors most often forget.
Common failures
- Publishing audio-only content — a podcast, interview, or announcement — with no transcript anywhere on the page.
- Providing a transcript that omits speaker identification, so readers cannot tell who is talking.
- Leaving out meaningful non-speech sounds (music, applause, a phone ringing) that hearing users perceive.
- Describing a silent video with a vague one-liner like 'video shows a process happening over time.'
- A video description that skips visual details a blind user needs to follow a demonstration or installation.
- Auto-generated captions or machine transcripts full of errors, treated as an equivalent alternative without review.
- Hiding the transcript behind a broken, keyboard-inaccessible, or hard-to-find control.
- Assuming a plain audio recording of an article counts, without clearly labeling it as a media alternative for the text.
- Leaving transcripts stale after the underlying audio or video has been edited or replaced.
How to test for 1.2.1
- 1
Inventory the prerecorded media
Find every <audio> element, embedded player, podcast, silent <video>, animation, and time-lapse. Automation rarely catches missing transcripts, so this is a manual sweep. Remember it applies to prerecorded content only.
- 2
Classify each file
Decide whether each item is audio-only or video-only, and whether it is informational or decorative. This tells you whether it needs a transcript, a text description, or an audio track.
- 3
Confirm an alternative exists and is findable
For each item, check that a transcript or description is present, close to the media, keyboard accessible, and clearly associated with it — not buried on another page.
- 4
Verify the alternative is equivalent
Read the transcript or description without the media. Does it include all spoken words, speaker labels, and meaningful sounds — or, for video, every visual action a sighted viewer would follow? Vague summaries fail.
- 5
Test with assistive technology
Navigate the transcript or description with a screen reader (NVDA, JAWS, VoiceOver). Confirm it reads in a logical order and that any audio-description track is announced and playable.
- 6
Check the labeled-alternative exception
If a recording re-presents on-page text, confirm the full text really is present and that the media is clearly labeled as an alternative to it. If either is missing, it fails.
For a structured audit, work through the full WCAG 2.2 checklist.
Related Success Criteria
Captions are provided for all prerecorded audio content in synchronized media.
Audio description or full text alternative is provided for prerecorded video content.
Captions are provided for all live audio content in synchronized media.
Audio description is provided for all prerecorded video content.
Sign language interpretation is provided for all prerecorded audio content.
Frequently asked questions
What does WCAG 1.2.1 require?
For prerecorded audio-only content, you must provide an alternative for time-based media — in practice, a text transcript — that presents equivalent information. For prerecorded video-only content (silent video), you must provide either a text alternative or an audio track that presents the equivalent information. There is one exception: if the audio or video is itself a media alternative for text and is clearly labeled as such, the criterion does not apply, because the text it presents is already available. It is a Level A criterion under Guideline 1.2 Time-based Media.
What is the difference between audio-only and video-only content?
Audio-only content is prerecorded media that has sound but no meaningful video — podcasts, interviews, recorded lectures, audiobooks, and audio announcements. Video-only content is prerecorded media that has moving pictures but no meaningful audio — silent animations, time-lapse footage, screen recordings without narration, and visual demonstrations. They need different alternatives: audio-only needs a transcript so deaf and hard-of-hearing users can read it, while video-only needs either a text description or an audio track so blind users can hear or read what is happening on screen.
What must a transcript for audio-only content contain?
A conforming transcript reproduces all spoken words verbatim and identifies who is speaking (for example [Host], [Guest]). It also describes non-speech sounds that carry meaning — [applause], [phone rings], [background music fades in] — because those sounds are part of the content for people who can hear them. Longer recordings benefit from timestamps and clear structure with headings and paragraphs. The test is equivalence: someone reading only the transcript should come away with the same information as someone listening to the audio.
Does video-only content need a transcript or an audio track?
Either one satisfies 1.2.1. You can provide a text description (sometimes called a text alternative for time-based media) that narrates every visual element and action in sequence, or you can add an audio track that describes what is happening as the video plays. A text description tends to be cheaper and also helps deaf-blind users reading braille, while an audio description track keeps the experience in the same medium. What matters is that the alternative conveys the same information a sighted viewer would get, not a vague summary like 'video shows a process happening over time.'
How is 1.2.1 different from captions (1.2.2) and audio description (1.2.5)?
1.2.1 covers media that is only audio or only video. Once a video has both a soundtrack and moving pictures (synchronized media), the relevant criteria are 1.2.2 Captions for the dialogue, 1.2.3 or 1.2.5 Audio Description for the visuals, and 1.2.4 for live captions. A transcript satisfies 1.2.1 for an audio-only file, but a transcript alone does not satisfy captions requirements for a normal video, because captions must be synchronized with the video timeline. Classify the media first, then apply the matching criterion.
When does the 'media alternative for text' exception apply?
The exception applies when the audio or video exists specifically to present information that is already available in text on the page, and it is clearly labeled as an alternative to that text. For example, an audio recording of an article that sits next to the full written article, labeled as the spoken version, does not need its own separate transcript — the article already is the text alternative. The label matters: users must be able to tell that the media is a media alternative for the text so they know the equivalent content is close by.