Can I convert SRT to WebVTT by renaming the file?

No. The header line has to be added and the decimal separator changed from comma to dot. A converter handles both.

Does WebVTT support styling?

Yes, through CSS applied to cues, and through inline tags within cue text. Support varies by player.

Which format should I upload to a video platform?

Most accept both. WebVTT is the better choice where positioning or styling matters; SRT is the safer default elsewhere.

Can WebVTT carry data that is not displayed?

Yes. Metadata tracks let you attach timed data to a video without showing it, which is used for things like chapter markers and synchronised page behaviour.

Definition

What Is WebVTT?

VideoText editorial team. Updated September 13, 2026.

Direct definition

WebVTT (Web Video Text Tracks) is a W3C subtitle and caption format for HTML5 video. A file begins with WEBVTT and uses cues with start and end times, typically with dot milliseconds.

The sections below explain how WebVTT is used in transcription and subtitle work, what people often mix up, and which VideoText workflow applies when the next step is a file or review pass.

Key takeaways

The first line must be WEBVTT.
WebVTT can carry voice spans, regions, and comments that SRT cannot.
Use a real converter between SRT and VTT.

How WebVTT works

A user agent (browser or player) parses the file as a text track, matches the current playback time to cues, and renders the cue text. The W3C Recommendation defines the syntax.

Example

WEBVTT 00:00:01.000 --> 00:00:04.000 Welcome to the recording.

What WebVTT adds over SRT

WebVTT was designed for the web and carries things SRT has no syntax for: cue positioning, alignment, styling through CSS, optional cue identifiers, regions for roll-up captions, and metadata tracks that need not be displayed at all.

It also allows comments and notes in the file, which is useful for production handover but must be stripped or ignored by players.

Practical differences that bite

The timestamp separator is a dot rather than a comma, and the file must begin with the WEBVTT header line. Renaming an SRT to .vtt therefore produces a file that looks right and fails to load.

WebVTT is the format HTML5 video expects natively, which is why it is the default for browser playback while SRT remains the safer interchange format between tools.

Frequently asked questions

Can I convert SRT to WebVTT by renaming the file?: No. The header line has to be added and the decimal separator changed from comma to dot. A converter handles both.
Does WebVTT support styling?: Yes, through CSS applied to cues, and through inline tags within cue text. Support varies by player.
Which format should I upload to a video platform?: Most accept both. WebVTT is the better choice where positioning or styling matters; SRT is the safer default elsewhere.
Can WebVTT carry data that is not displayed?: Yes. Metadata tracks let you attach timed data to a video without showing it, which is used for things like chapter markers and synchronised page behaviour.

Related terms

Sources

W3C: WebVTT: The Web Video Text Tracks Format (W3C Recommendation)