Open captions are syncronized text that is integrated in the video's visual content. They cannot be turned off. Closed captions (CC) are syncronized text that must be enabled by the user to view. These can be turned on or off.

Whether the captions or open or closed, they should be 99% accurate for all audio and video content. Use these general guidelines and best practices:

• Use appropriate grammer, spelling, and punctuation
• Use a consistent style for identifiying speakers, sound effects, and music.
• Speakers should speak at a normal or slow pace for more accurate captioning and more time for viewers to read the captions.
• No more than 2 lines at a time and no more than 45 characters per line.
• Adjust line breaks so captions starts and ends with a period or comma.
• Include filler words when possible.
• If an excessive amount of filler words obscure the meaning of the content, omit them.
• Use brackets to indicate sound effects.
• Use ellipses to indicate lack of sound that lasts 3 or more seconds.
• Identify speakers with parentheses or their name followed by a colon.
• Caption all profanity that is audible. If the profanity is censored, then censor it in the captions too.
• If audio can not be interpretted, indicate with [inaudible].

Section508.gov. (2025). Section508.Gov. https://www.section508.gov/create/captions-transcripts/

Transcripts differ from captions they are viewed separately from the video and audio content. A document that describes audio-only and video-only content is a transcript. Transcripts typically follow the same guidelines as captions with these additions:

• It must be provided in an accessible file type such as MS Word (docx) or text file (txt).
• It must be located in the same place as the video.

Section508.gov. (2025). Section508.Gov. https://www.section508.gov/create/captions-transcripts/

Audio descriptions audibly describe visual content that cannot be interpreted by people with low or no vision. This is significant in videos that describe steps for solving problems or performing a task because if the narrator only says "click here... then drag it here... then this cancels this," it tells a user with a visual impairment absolutely nothing about what is going on in the video. Because of this, it is imperative to describe all relevant visual details presented in the video.

Generally, if the steps cannot be completed with just the audio of the video, then there is not a good enough description of the visual details.

Use these guidelines:

• Describe landmarks (ribbon, side bar, tool bar, etc.) by their name in addition to their color, location, or shape.
• Describe instructions that do not rely on sounds.

Captions or text presented in the video should have a color contrast ratio of 4.5:1. This can be measured with WebAIM's Color Contrast Checker.

Videos that last more than 5 seconds or audio that lasts more than 3 seconds should be able to paused, stopped, muted, or hidden by the user.

Video content should not flash more than 3 times per second.