Web Accessibility

Multimedia (Audio & Video)

When including multimedia (audio or video) on your website or within course materials, it is important to consider accessibility, as well as the time and costs associated with producing captions and/or transcripts.


Captions are text versions of the spoken words and important sounds presented within a video. Captions allow the content of web audio and video to be accessible to those who do not have access to audio. They should contain descriptions, explanations, or comments that may be beneficial, such as indications of laughter or an explosion.

Common web accessibility guidelines indicate that captions should be:

  • Synchronized: The text content should appear at approximately the same time that audio would be available

  • Equivalent: Content provided in captions should be equivalent to that of the spoken word

  • Accessible: Caption content should be readily accessible and available to those who need it

Captions can be either closed or open. Closed captions can be turned on or off, whereas open captions are always visible. Additionally, captions increase view time and focus, and enhance comprehension and engagement.


A transcript is a written version of an entire video (like a screenplay) or audio file, and should include descriptions of important sounds and visual elements. Transcripts allow those who cannot access content from audio or video to read (or listen to) a text version instead. The transcript text is also searchable, both by computers (such as search engines) and by end users.   

Both captions and transcripts make your video more likely to be found by search engines, help those who prefer to learn or retain information by reading, and assist users learning a new language.