Under WCAG 2.1 Level AA, prerecorded video content must include audio description when important visual information is not otherwise provided through narration or dialogue. Audio description ensures that individuals who are blind or have low vision can access the same information conveyed visually in a video.
UMB Standards
Audio description is required for prerecorded video when visual elements convey essential information that is not spoken aloud (e.g., on-screen text, charts, graphics, demonstrations, or silent actions).
Audio description is not required when the narration or dialogue already clearly conveys all information shown visually.
Acceptable Approaches
Acceptable approaches to meeting this requirement include:
- Integrated description: The video’s narration naturally describes important visual elements as part of the script.
- Audio description track: Upload an audio description file to your YouTube or Vimeo video.
- Alternate version with audio description: A second version of the video that includes audio description mixed into the main soundtrack (clearly labeled “Video with Audio Description”).
- Descriptive transcript: A transcript that includes spoken dialogue and descriptions of key visuals. (This is helpful and may meet other WCAG needs, but Level AA expectations for prerecorded video typically require audio description when visuals are not otherwise conveyed in audio.)
When platform limitations prevent the use of audio description tracks, schools and units must ensure effective communication through alternative accessible methods.
Responsibility for ensuring compliance with audio description requirements rests with the account’s owner for accounts representing its programs, departments, offices, and centers.
Live video
Audio description is recommended but not required for live video content under WCAG.
Best practice is to verbally describe key visuals during live presentations whenever feasible.
Live video made available for replay (recorded/archived)
Once a livestream is posted for on-demand viewing, it becomes prerecorded video content. If the replay includes important visual information that is not communicated through the original narration, you must provide an accessible solution consistent with prerecorded video requirements under WCAG 2.1 AA as described under Acceptable Approaches.
Determine if Audio Description Is Needed
Most social media platforms do not support multiple audio tracks, making it difficult to add a separate audio description track.
First, determine if audio description is needed.
Does the video have visual information that is required to understand the message?
- If NO (Example: a person speaking directly to camera with no meaningful visual changes)
- Audio description is not required.
- Best practice: Ensure that the spoken narration fully conveys the message.
- If YES
- Pre-recorded video
- Audio description is required under WCAG 2.1 Level AA.
- A descriptive transcript may satisfy Level A, but Level AA expects audio description unless all visuals are already explained verbally.
- Live video
- Audio description is recommended but not required under WCAG.
- Best practice is to verbally describe key visuals during the livestream.
- Live replay/on-demand recording
- Treat as prerecorded video and provide an accessible solution.
- Pre-recorded video
Preferred Solution: Integrated Description
Whenever possible, use integrated description, which means writing the video script so that visual information is naturally described as part of the narration.
This approach is recommended by W3C and often eliminates the need for a separate audio description track.
Examples
- Have speakers identify themselves and their role aloud (not only via on-screen text).
- Read out essential on-screen text (names, dates, key results, calls to action).
- When showing data, summarize the takeaway in plain language.
Reference: Audio Content and Video Content | Web Accessibility Initiative (WAI) | W3C
When Integrated Description Is Not Possible
If integrated description cannot reasonably be added, use one of the following options:
Option A: Host on a platform that supports descriptive audio tracks (when appropriate)
If you control the hosting environment and it supports multiple audio tracks, you may be able to provide descriptive audio as a separate track on YouTube and Vimeo. This is the preferred option.
Option B: Descriptive Transcript or Social Media Caption
Write in your social media post descriptions of important visuals.
Provide a transcript that includes spoken dialogue and descriptions of important visuals.
Link to the transcript from the post caption, comments, or a landing page that is accessible.
Use this especially when platform limitations make other options impractical (and as a supplement to strengthen effective communication).
Option C: Alternate Version with Audio Description
Because most social platforms do not support separate audio tracks, the most reliable approach is to:
- Create a second version of the video that includes audio description mixed into the main soundtrack. It’s OK to host this on YouTube or Vimeo and not the original social media platform.
- Label clearly in the caption and/or title: “Video with Audio Description.”
Platform Considerations
For platforms like Instagram, Facebook, LinkedIn, TikTok, and X (and most short-form social video workflows), assume no separate descriptive audio track is available. Use one of these approaches:
- Integrate description into the narration (preferred)
- Publish an alternate, audio-described version (recommended when visuals are essential)
- Provide a descriptive transcript via an accessible link (supporting option)
YouTube may support adding a descriptive audio track through YouTube Studio’s Languages workflow, depending on feature availability for your channel/account.
If your channel does not have access to multi-audio/descriptive audio features, publish an alternate audio-described version of the video and clearly label it as described.
Writing Audio Descriptions
What to Include
Focus on what the listener needs to know to understand the video’s message:
- Who is speaking (names/roles when not already clear in audio)
- Key actions (what is happening, movement, demonstrations)
- Setting and scene details when they add context
- Facial expressions or reactions when they affect meaning
- Charts/graphics and on-screen text that communicate key information
Avoid describing decorative visuals that do not add meaning.
Writing Tips
Use these guidelines to keep audio descriptions clear and useful:
- Describe what is observable (not assumptions about motives or feelings).
- Use present tense and describe actions as they happen.
- Keep it concise and focused on meaning.
- Use plain language and avoid jargon when possible.
- Aim for natural pauses in the original audio so the description fits smoothly.
- If you cannot fit essential information into natural pauses, consider extended audio description (where the video effectively includes additional time to accommodate the description).
Standard and Extended Audio Description
For most social video, standard description (or scripting descriptions into the narration) is the most practical approach.
- Standard audio description: Fits within natural pauses in existing audio.
- Extended audio description: Adds time/space for description when the video has few pauses or dense visual content.
How to Add a Descriptive Audio Track on YouTube
Video: How to Add Audio Description to YouTube Videos (3Play Media)
If your channel has access to descriptive audio/multi-audio features:
- Sign in to YouTube Studio (desktop).
- In the left menu, select Languages.
- Click the video you want to edit.
- Select the language you are editing.
- Find Descriptive audio and choose Add, then select your file and upload.
- Publish your changes.
Important note from YouTube: To add a descriptive audio track, you must already have the original or dubbed audio track uploaded in the same language.
If you need to replace an audio file later, YouTube also documents delete/replace steps in the Languages workflow.
If the descriptive audio option is not visible in YouTube Studio:
Use the alternate version approach (upload a separate “Video with Audio Description” version), and label it clearly.
No Fully Automated Compliance Tool Exists
There is currently no tool that can automatically determine whether a video requires an audio description track under WCAG 2.1 AA.
Third-party vendors offer at a cost, assisted software to generate audio description. UMB is exploring vendor options that are approved for use.
Automated tools can assist with analysis, but final determination must be made by a content creator or reviewer.
Tools That Can Assist (But Not Decide)
While no tool can make the compliance decision, the following tools can help staff compare spoken content to visual content:
- Speech-to-text/transcript tools
- YouTube auto-captions
- Otter.ai
- Descript
- Rev
- Visual analysis tools
- Microsoft Azure Video Indexer
- Google Video AI
- AWS Rekognition
- Descript’s scene analysis features using Underlord AI chatbot
These tools can:
- Identify spoken dialogue
- Detect on-screen text
- Flag visual scenes or actions
They cannot determine whether those visuals are essential — that decision remains with the reviewer.
Recommended Review Workflow
Use the following semi-automated workflow to determine whether audio description is required:
- Generate a transcript
- Use YouTube, Descript, or Otter.ai.
- Edit for accuracy (~99%).
- Review the visuals
- Watch the video without sound or
- Use a visual analysis tool to identify on-screen text, charts, or silent actions.
- Compare transcript to visuals
- Ask: Does the transcript fully communicate what the visuals show?
- Make a determination
- If yes → Integrated description or narration is sufficient.
- If no → Audio description, descriptive transcript, or alternate upload is required.
This process should be documented when applicable to demonstrate good-faith compliance.
Best Practices
Plan for accessibility during scripting and storyboarding, not after editing.
Default to integrated description whenever possible by describing visuals naturally in narration.
Do not rely on automated tools alone to determine whether audio description is required.
Use transcripts and visual review together to assess whether visuals convey essential information.
When platforms do not support multiple audio tracks:
- Provide integrated description, or
- Publish a descriptive transcript, or
- Upload a second, audio-described version of the video (YouTube), or
- Host on a platform that supports multiple tracks (Vimeo).
Clearly label accessible versions (e.g., “Video with Audio Description”).
Document the decision-making process and solution used to demonstrate reasonable efforts and effective communication.