SBV (YouTube) to SRT
Convert SBV to SRT subtitles. Cue timings are re-parsed and re-formatted exactly, not merely re-punctuated. ASS/SSA override tags ({\i1}, {\an8}, ...) are carried through as literal text, not re-rendered or stripped. Use Strip subtitle formatting for that. VTT cue settings (align, position, line, size, ...) are dropped, not preserved. This converter carries dialogue and timing, not layout. Runs on your device.
Runs on your device. The file is never uploaded.
SBV (YouTube) to SRT reads each block of an .sbv caption file and writes SRT, numbering the cues from 1 in file order. Both formats hold milliseconds, so nothing is rounded; the hour gains its padding and the fraction a comma. A block whose first line is not two comma-separated timestamps stops the run.
Questions
Why does it say a cue has no start,end timing line?
Because the first line of that block is not two timestamps separated by a comma, which is how SBV marks a cue. The message quotes the line it choked on. A common cause is a file that is SRT or VTT with an .sbv name; in that case use SRT to VTT or VTT to SRT instead.
Are the timings exact?
Yes. SBV and SRT both record milliseconds, so every timestamp is parsed into milliseconds and rewritten in SRT form with the hour padded to two digits and a comma before the milliseconds. No rounding happens in this direction. That is a real difference from the ASS direction, where the format itself records only centiseconds and rounding cannot be avoided.
Does it add cue numbers?
Yes. SBV has no numbering, so SRT numbers are generated in file order starting at 1. Cue text is copied unchanged, including anything that looks like a tag, since this tool moves dialogue and timing and does not rewrite your words.
Can I fix caption timing at the same time?
Not in this tool, but Shift subtitle timing moves every cue by a fixed offset in milliseconds and works directly on SBV as well as SRT, so you can shift before or after converting. Split subtitles by time and Merge subtitle tracks also read SBV.
What is the output file called?
Your file name with .srt in place of .sbv, so captions.sbv becomes captions.srt. The SRT text is also shown on the page. Nothing is uploaded: the whole conversion is plain parsing and formatting inside this tab. One file goes in per run, so run it again for the next set of captions; nothing is kept between runs.