Is There a Tool to Shift Subtitle Timing by a Few Seconds All at Once?
Yes. CaptionIt lets you shift all subtitle lines by a set number of seconds in one pass, so if your captions are running early or late across the whole file, you fix it once instead of editing every line. It works directly in your browser, and the file never gets uploaded anywhere.
What "shift timing" means here
If every line in your SRT or WebVTT file is off by the same amount — say captions appear 3 seconds too early for the whole video — you enter that offset once and CaptionIt applies it to every timestamp in the file. This is different from fixing individual lines that drift out of sync at different points; CaptionIt also pulls those back into line, but the all-at-once shift is a single-number adjustment.
How it works in practice
You open your subtitle file in CaptionIt, enter the offset in seconds (positive to delay, negative to move earlier), and it rewrites all the timestamps at once. No command line, no manual math per line.
Works with SRT and WebVTT
CaptionIt reads and writes both SRT and WebVTT, and converts between the two formats. The timing shift works the same way regardless of which format you start or end with.
No transcript yet? It can build one
If you don't have captions at all, CaptionIt can generate a timed transcript from the audio itself. This is charged by the minute, with the first 30 seconds free to test on your own file before committing.
Nothing is uploaded
The file processing — including the timing shift — happens in your own browser. CaptionIt does not send your subtitle file to a server to do this. If you need a documented data-processing guarantee for compliance reasons, check your own organisation's requirements, since this description covers how the tool works, not a formal certification.
Frequently asked questions
Is there a tool to shift subtitle timing by a few seconds all at once?
Yes. CaptionIt applies a single offset — in seconds — to every line in an SRT or WebVTT file at once.
Can I shift subtitles earlier instead of later?
Yes. Enter a negative offset to move all timestamps earlier, or a positive one to delay them.
Does this work if only part of the subtitle file is out of sync?
A flat shift moves everything equally, so it's for files where the whole thing is off by the same amount. If the drift varies through the file, CaptionIt's sync-correction feature handles that case instead.
Do I need to upload my subtitle file to use this?
No. The shift happens in your browser; the file isn't sent to a server for this step.
What if I don't have a subtitle file yet, just a video or audio?
CaptionIt can generate a timed transcript from the audio, charged per minute, with the first 30 seconds free to try.
Which subtitle formats does the timing shift support?
SRT and WebVTT, including converting between the two.