Add Video Captions

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When adding a video to your activity, you can upload video captions to ensure the video is accessible for your students.

To add captions, you will create and upload a Video Text Track (vtt) file. If it’s helpful, you can also download this example.vtt file and edit in a text editor. We’ve also used this VTT creation website to create caption files.

The activity Playing Catch Up is also a good place to find an example of video captions in an activity.

If you have any questions or feedback about adding captions to videos in your activities, we'd love to hear at

Video caption in activity builder.


Caption text in a text editor

Start from the example file.

Download and open the example.vtt file in a text editor. Make sure the file name ends in “.vtt” when uploading to your video.

VTT text in a text editor

Keep each caption short enough to read.

Each caption should be no longer than 3 lines of text and no more than 32 characters. Captions should be visible for 3-7 seconds.

VTT text in a text editor

Include sounds and speaker changes in the captions.

Help viewers understand what is going on in the video by captioning sounds, (ie [Laughter]). When the speaker changes, include a dash before the new text to indicate that the speaker has changed. More caption writing tips.

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