Free, instant, and entirely in your browser — your subtitle file is never uploaded.
MicroDVD counts frames, not seconds — this has to match the video.
SBV is YouTube's own caption format, and about as simple as SRT with one line less: no sequence number, and the two timestamps separated by a comma rather than an arrow.
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.
Captions leaving YouTube for a site you control. People arrive here after downloading their own subtitles out of YouTube Studio — often because they are moving a video to Vimeo, a course platform, or a plain HTML5 player — and discovering that SBV means nothing outside Google's own tools. The conversion is clean in both directions of meaning: same text, same times, written the way a browser expects. Remember to point your <track> element at the new file and give it a srclang.
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 SBV 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.
Captions leaving YouTube for a site you control. People arrive here after downloading their own subtitles out of YouTube Studio — often because they are moving a video to Vimeo, a course platform, or a plain HTML5 player — and discovering that SBV means nothing outside Google's own tools. The conversion is clean in both directions of meaning: same text, same times, written the way a browser expects. Remember to point your <track> element at the new file and give it a srclang.
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 SBV, it says so and points you at the all-format converter instead of producing a broken file.