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Subtitle Time Shifter

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Fixes subtitles that lag or run ahead of the audio. Paste your `.srt` or `.vtt` content, set a positive offset (push cues later) or negative offset (pull cues earlier — use a decimal like `-1.5`), and the entire file is re-emitted with timestamps updated. Format is auto-detected by looking for the `WEBVTT` header; the comma vs. dot in the timestamps switches accordingly.

Shifted (cues shifted: 3)
1
00:00:01,200 --> 00:00:04,000
Hello, world.

2
00:00:05,500 --> 00:00:08,800
Subtitle Time Shifter
demo input.

3
00:00:09,000 --> 00:00:11,500
Adjust the offset above.

Cue text, blank lines, NOTE / STYLE blocks, and cue numbering pass through untouched.

How to use

  1. Paste the contents of your subtitle file in the input box.
  2. Enter the offset in seconds — decimals welcome (`0.5`, `-1.25`).
  3. Copy the output back into your subtitle file. The cue count is shown so you can sanity-check.

Frequently asked questions

How do I figure out the right offset?
Play the video and note where line 1 of the subtitles *should* start. Subtract its current start time from that target. If the subtitle says 00:00:02.000 but should appear at 00:00:03.500, the offset is +1.5.
What happens to cues that would land before 00:00:00?
With `Clamp at zero` on (default), those cues are pinned at 00:00:00 so the file stays valid. Turn it off if you'd rather see an explicit error — useful when you want to know your offset is too aggressive.
Does it touch the cue text?
No. Only lines that match the `start --> end` timestamp pattern are rewritten. Subtitle text, blank lines, the `WEBVTT` header, NOTE blocks, STYLE blocks, and cue numbering pass through unchanged.
What about VTT cue settings like `align:start`?
Preserved. Anything after the second timestamp on the cue-timing line is kept verbatim.

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