Correct timestamps
SRT’s comma milliseconds become WebVTT’s dot milliseconds, cue by cue.
SRT is the older, simpler format: numbered cues, comma-separated milliseconds, plain text. WebVTT is the format the web standardized on: it is what the HTML track element requires, which makes it the format HTML5 players, and most modern platforms, expect.
WebVTT starts with a WEBVTT header, uses a dot for timestamp milliseconds, and omits sequence numbers. It can also contain cue positions, style hooks, and metadata notes. A web player that requires VTT can reject an SRT file.
This converter runs in your browser and does not upload the file. Local processing protects unreleased product names, internal training content, and other private caption text.
If your captions misbehave after conversion, the problem usually predates it: overlapping cues, reversed timestamps, or blank entries in the source file. The caption validator checks for all of those and repairs the safe ones.