What Is a VTT File?
A VTT (WebVTT) file is a plain-text caption file that stores subtitles with timecodes and styling for web video — similar to SRT, but built for the web.
A VTT file — short for WebVTT (Web Video Text Tracks) — is a plain-text file that stores a video’s captions or subtitles together with the timecodes that sync each line to the audio. It’s the native caption format for HTML5 web video.
VTT vs. SRT
VTT and the older SRT file do the same core job — carry timed caption text — but differ in a few ways:
- Header — a VTT file begins with a
WEBVTTline; SRT files don’t. - Styling — VTT supports positioning, colors, and basic formatting; SRT is plain text only.
- Support — SRT is accepted almost everywhere; VTT is the standard specifically for HTML5
<track>elements on the web.
For most social platforms, SRT is the safe upload format; VTT is common when you’re embedding video on your own website.
Why caption files matter
Whether VTT or SRT, a separate caption file powers toggleable closed captions — the kind viewers can switch on or off. They make your content accessible, improve watch time on muted feeds, and give search engines readable text about your video.
Generating captions without the busywork
quso.ai exports subtitles as SRT, not VTT. Its SRT file generator transcribes your video and downloads an editable .srt on paid plans, which converts to VTT easily: add a WEBVTT line at the top and swap the comma in each timestamp for a dot. The AI subtitle generator covers 99 languages for captions on web video and social posts.