Free, instant, and entirely in your browser — your subtitle file is never uploaded.
MicroDVD counts frames, not seconds — this has to match the video.
Plain text is the subtitle with the subtitle part removed: the spoken lines, in order, with no timing at all.
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.
You have the words your video says and you want them on YouTube. This produces a valid SBV with one cue per line in sequence, which is enough for the file to upload and open in YouTube Studio — but the timing is arithmetic, not transcription, so it will not match the speech. There is a better route if it is available to you: upload the plain transcript to YouTube directly and let its aligner time it against the audio. Use this when you need an SBV file itself, and expect to adjust it.
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.
Plain text has no timing, so this conversion has to invent it. Each line becomes a cue of a fixed length, laid end to end from the start of the file. The words will be right and the timing will not — it is a scaffold, not a finished subtitle. The honest workflow is to convert here, then open the result in a sync tool and line it up against the video.
No. The conversion runs in your browser using JavaScript — your TXT 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.
You have the words your video says and you want them on YouTube. This produces a valid SBV with one cue per line in sequence, which is enough for the file to upload and open in YouTube Studio — but the timing is arithmetic, not transcription, so it will not match the speech. There is a better route if it is available to you: upload the plain transcript to YouTube directly and let its aligner time it against the audio. Use this when you need an SBV file itself, and expect to adjust it.
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 TXT, it says so and points you at the all-format converter instead of producing a broken file.