webVTT files for Video Captions or Descriptions Last Updated October 2025 A WebVTT or Web Video Text Track is a file format for displaying timed text, such as subtitles, captions and audio description for video content on the internet. The file type can be added to a video file in the HTML code or added to a Vimeo or YouTube video. On this page: Create Your File Components of the File Validate Your File Examples File with Description Statement Basic file with Multiple Cues Basic file with Optional Header File with Advanced Time Code Settings Styles & Questions Create Your File Create the WebVTT file in your favorite text editor (for example TextEdit on Mac). To get started, you can copy one of the examples below into your file and update the timecode and text to be appropriate for your video. When you are finished, save your file with the extension .txt. Then change the file’s extension from .txt to .vtt. Finally, change the file to plain text in Textedit: Go to Format -> Make Plain Text. If your video is short, does not have dialog, or convey chronological sequences of information, then the file kind can most likely be a description and simply summarize the video. see the File with Description Statement Example, below. Components of the File Required first line of a webVTT file A basic WebVTT file needs to start with the string WEBVTT at the top of your document. Cues Each webVTT contains block(s) called cues. A basic Cue contains four things: A cue identifier to help you organize your captions, such as sequential numbers or letters. Time code for where in your video’s timeline your text is to be displayed. The actual text that is displayed on the screen. See Tips for Writing Captions & Audio Description There needs to be a blank line in between each subtitle block. NOTE that you can have multiple captions in a single time range. Optional header To help you visually organize multiple VTT files, an optional header can be added to the left of the initial WEBVTT string. The only character restriction is that your header cannot contain the following string of characters, which is reserved for cues only: ---> So, if you are going to use a header it is best to just give it a dash as demonstrated in the example with the optional header below. Understanding Time Codes The time codes are displayed as hours, minutes, seconds and millli-seconds rounded to three digits, 00:00:00.000 (hh:mm:ss.fff). Hours can be optional. Since hours can be optional the times are frequently displayed as 00:00.000 (mm:ss.fff). The first time code, presented before -->, represents when the text should appear on the screen. The second time code, presented after -->, the end time. Be sure to provide ample time for visitors to read each cue. Validate Your File You can validate your file on this site at no cost to check it: https://tools.igem.org/wiki/vtt-validator Examples File with Description Statement WEBVTT 1 00:00:01.000 --> 00:15.000 Several clips from recent productions, events and courses. A celebration of the vibrant community of our Department and the work that we do. Basic file of multiple Cues WEBVTT 1 00:00:01.000 --> 00:09.000 Music from Symphony No. 2 for Wind Ensemble 2 00:01.000 --> 00:09.000 Movement, creativity and energy throughout the department. Basic file with Optional Header WEBVTT -En Vogue, My Lovin' (You're Never Gonna Get It), Funky Divas, 1992 1 00:01.000 --> 00:04.000 Now you promise me the moon and stars 2 00:05.000 --> 00:09.000 Save your breath, you won't get very far (Oooh, bop..) File with Advanced Time Code Settings Using the following method you can get very specific with where in your video’s timeline you’d like specific text to appear. WEBVTT 00:00:00.000 --> 00:00:07.000 This <00:00:01.000>text <00:00:02.000>will <00:00:03.000>appear <00:00:04.000>over <00:00:05.000>6 <00:00:06.000>seconds. Styles & Questions The style of the text on the screen can be set in the cue block but most styles will be determined by the website style guides and the CSS for your website. If you would like to change the styles or have questions about getting started with WebVTT files, please contact your College of Fine Arts Web Team at cofawebmaster@austin.utexas.edu.
