When you need VTT
Web players (the HTML5 `<track>` element), YouTube subtitle upload, and most browser-based players accept VTT (WebVTT) only — not SRT. If all you have is SRT, one conversion makes it work.
How the two formats differ
The content is nearly identical; three things are written differently: the WEBVTT header line (required in VTT); the millisecond separator in timestamps — SRT uses a comma (00:00:01,000) while VTT uses a dot (00:00:01.000); and VTT allows NOTE and STYLE blocks that SRT does not.
How to convert
Open the converter, drop in the SRT, choose VTT - WebVTT as the output, then convert and download. Cue order, timing values, and multi-line text are all kept as-is — only the syntax changes. Going the other way? See VTT to SRT.