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*Details: File format summary



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Name Web Video Text Tracks (WebVTT) Format
Other names  
Identifiers PUID:  fmt/1454
MIME:  text/vtt
Classification Text (Structured)
Description WebVTT files are used for captioning or subtitling video content. It is a standard created by the World Wide Web Consortium (W3C) for displaying timed text, and is linked to the HTML5 <track> element. The primary purpose of WebVTT files is to add text overlays to a video. Each time interval is specified in the format (HH:) --> (HH:)mm:ss:xxx e.g. 00:00.000 --> 00:02.310 or 01:00:05.000 --> 01:00:07.000. The (HH:) is optional, but if included must have a minimum of 2 digits representing the hour (more than 2 digits may be used), and where both the minute (mm) and second (ss) parts must be between 00 and 59 inclusive.
Byte order  
Related file formats None.
Technical Environment  
Supported until  
Format Risk  
Developed by W3C / W3C
Supported by W3C / W3C
Source date 16 Nov 2020
Source description  
Last updated 13 Mar 2023
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