Free, instant, and entirely in your browser — your subtitle file is never uploaded.
MicroDVD counts frames, not seconds — this has to match the video.
SRT is the plainest subtitle format there is: a number, a start and end time, the lines of text, a blank line, repeat. It came out of a 1990s DVD-ripping program called SubRip and has outlived every format designed to replace it, precisely because there is almost nothing in it to go wrong.
WebVTT is SRT rebuilt for the web: the same cue structure, a WEBVTT header line, a dot instead of a comma before the milliseconds, and optional positioning settings after the timestamp. It is the only subtitle format HTML5 video natively understands.
This is the conversion you need to put subtitles on your own website. The two formats are so close that the file barely changes — a WEBVTT line at the top, dots instead of commas before the milliseconds — but a browser will refuse the SRT and accept the VTT, and that is the whole point. Nothing about the text or the timing is touched.
You want WebVTT because the subtitle has to work in a browser. An HTML5 <track> element reads VTT and nothing else, and HLS and DASH streams expect it too. If you are putting a video on your own site, or feeding a web player, this is the conversion that makes captions appear at all.
Both sides carry the same thing — lines of text with a start and an end — so this is the cleanest conversion in the set. Nothing is approximated and nothing is thrown away; the timestamps are rewritten in the target's notation and the text goes across as it stands. What changes is compatibility: which players, platforms and browsers will accept the file you end up with.
No. The conversion runs in your browser using JavaScript — your SRT file is read from disk, converted in memory and handed back as a download. Nothing is transmitted, so there is nothing for us to store or delete. You can disconnect from the internet after this page loads and the conversion still works.
This is the conversion you need to put subtitles on your own website. The two formats are so close that the file barely changes — a WEBVTT line at the top, dots instead of commas before the milliseconds — but a browser will refuse the SRT and accept the VTT, and that is the whole point. Nothing about the text or the timing is touched.
The page checks before it converts. Subtitle formats are identified by what is inside the file rather than by the extension — which matters, because .sub alone is used by three unrelated formats. If you hand this page something that is not SRT, it says so and points you at the all-format converter instead of producing a broken file.