Free, instant, and entirely in your browser — your subtitle file is never uploaded.
MicroDVD counts frames, not seconds — this has to match the video.
MicroDVD is the odd one out: it counts frames, not time. Each line is {start}{end} followed by the text, with a pipe between display lines. There is no timestamp anywhere in the file.
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.
Two formats that could hardly be further apart in time: MicroDVD belongs to the era of burned discs and DivX players, SBV to YouTube's caption editor. Getting from one to the other means turning frame counts back into clock times first, so the frame rate above decides whether the result lands on the dialogue or slides past it. Check the first and last lines against the video after uploading — a rate that is merely close will look fine at the start and be seconds out by the end.
You want SBV because you are uploading to YouTube and want the format its own editor writes. It is worth knowing this is rarely necessary — YouTube accepts SRT quite happily — so choose SBV when a workflow or a tool specifically asks for it, not as a default.
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. Because MicroDVD is the source here, the frame rate is something the file does not reliably tell you. The numbers inside it are frame counts, and turning them back into seconds requires the rate the file was authored for. Many of these files declare it on a leading {1}{1} line, and when yours does that value is used automatically. When it does not, the figure above is an assumption — if the result drifts steadily rather than sitting at a constant offset, that assumption is what to change.
No. The conversion runs in your browser using JavaScript — your SUB 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.
Two formats that could hardly be further apart in time: MicroDVD belongs to the era of burned discs and DivX players, SBV to YouTube's caption editor. Getting from one to the other means turning frame counts back into clock times first, so the frame rate above decides whether the result lands on the dialogue or slides past it. Check the first and last lines against the video after uploading — a rate that is merely close will look fine at the start and be seconds out by the end.
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 SUB, it says so and points you at the all-format converter instead of producing a broken file.