Captions are a text equivalent of audio, shown at the same time as the audio (usually a few lines at a time).
Captions make video accessible by providing a text version of spoken dialog and meaningful sound for people who can't hear or process the original sound. They usually include:
- Speech
- Music
- Sound effects
- Speaker identifications
- Any important information that is conveyed in sound
Captions are used by people who are D/deaf, have hearing loss, are less familiar with the language or topic, process text better than audio, or are in a noisy environment.
Captions are required for video, whether live-streamed or pre-recorded, by digital accessibility standards, as described in Success Criterion 1.2.2 Captions (Prerecorded) and 1.2.4 Captions (Live).
Best Practices
Videos require quality captions to provide equitable access for people who rely on captions. Quality captions are:
Accurate
Captions should correctly represent audio information without errors in wording, spelling, or punctuation.
In general, the goal is to work towards error-free captions, so people who rely on captions get the same information, and equitable access.
Consistent
Understandable and predictable captions, with consistent language and visual presentation, are easier to use.
The goal is to avoid unexpected changes or confusion. For example, captions should use the same speaker identification throughout, not start with “Ono” and change to “President.”
Complete
Captions must include all the meaningful information in the audio, from the beginning to end. This includes:
- Speaker identifications
- Non-speech information (such as laughter, applause, music, and more)
Captions should not summarize, censor, or change the original content, unless necessary to make them readable (for example, to make the text fit on the screen).
Usable
Captions must be readable for the people who need them. This means that captions are:
- displayed with enough time to be read completely
- in sync with the audio
- not blocked by (and not blocking) the visual content, including text on screen
In general, closed captions (that can be turned on or off, and adjusted for size and display) are more usable than open captions (burned into the video’s visual image). Open captions should be used only when people cannot control the media player, such as digital signage.
Create Captions
Visit How To: Make Video & Audio Accessible to learn about creating captions.