About this tool
What Subtitle Time Shift does
Move every subtitle cue earlier or later by the same number of seconds. Paste an SRT or VTT file, enter an offset such as -1.5 or 2.5, then download a file that stays in sync. Nothing is uploaded and the text never changes.
- One offset moves the whole fileEnter 2.5 to delay the subtitles by two and a half seconds, or -1.2 to bring them forward. Every cue moves by the same amount, so the internal rhythm of the dialogue is preserved instead of being re-timed cue by cue.
- Nothing is dropped when the offset is negativeA cue that would start before 00:00:00 is pinned to zero and keeps its original duration instead of disappearing. The result area reports how many cues were clamped, so you can decide whether that is acceptable.
- Text, numbering and formatting stay untouchedOnly timestamps are rewritten. Dialogue, cue order, italic and bold spans remain exactly as written, and the output keeps the standard cue blocks that desktop players and editing software expect.
- The result tells you what changedNext to the output you get the cue count, the new time range and any wording the checker flags, so you can confirm the shift landed where you expected before downloading the file.
- Messy files are read, not rejectedSRT and WebVTT share the same parser as the converters: missing blank lines between cues, short millisecond fields, and comma or dot separators are normalised rather than refused with an error.
- Built for the usual sync complaintsA constant offset, an intro card added after the subtitles were timed, or a re-encoded video that starts slightly later: as long as the error is the same everywhere, one number fixes the whole file.
Quick guide
How to use Subtitle Time Shift
- 1
Add your subtitle file
Choose an .srt or .vtt file, drag it into the workspace, or paste the cue text.
- 2
Enter the offset in seconds
Positive delays the subtitles, negative brings them forward. Decimals such as 0.5 or -2.25 are allowed.
- 3
Check the numbers, then save
Confirm the new time range and the warning count, then copy the result or download the shifted file.
Example
Before and after
1 00:00:10,000 --> 00:00:12,000 First line 2 00:00:14,500 --> 00:00:16,000 Second line
1 00:00:12,500 --> 00:00:14,500 First line 2 00:00:17,000 --> 00:00:18,500 Second line
FAQ
Frequently asked questions
Which direction is positive?
Positive moves subtitles later, so they appear after the picture; negative moves them earlier. If the dialogue is already spoken when the text appears, you need a positive offset.
My subtitles are 12 seconds behind the audio. What do I enter?
Enter 12 to push every cue twelve seconds later. If the subtitles show up twelve seconds before anybody speaks, enter -12 instead.
The gap grows through the video. Can this tool fix that?
No. This tool applies one constant offset. When the delay increases over time the file needs linear re-timing, which is a different calculation; changing the offset here would fix one scene and break another.
Will my cue text change?
No. Only start and end times are rewritten. Dialogue, numbering and inline styling are preserved exactly, and no cue is merged or split.
What happens if a negative offset pushes a cue before zero?
That cue starts at 00:00:00 and keeps its original duration, and the page reports how many cues were clamped. Nothing silently disappears.
Does it work with both SRT and WebVTT?
Yes. Both are accepted and the output is SRT, so it opens in desktop players and editors. Convert to WebVTT afterwards if the file is going onto a web page.
Can I shift by a fraction of a second?
Yes. Decimals are fine: 0.4, 1.5 or -2.25. The value is converted to milliseconds before it is applied, so the result is exact.
Are my files uploaded?
No. The file is read and rewritten inside your browser. ToolPouch never receives the subtitles and nothing is stored on a server.
How is this different from an editor's retime tool?
Some editors also change cue durations or merge overlapping cues. This tool only adds the same amount to every time value, which makes it predictable and reversible: apply the opposite offset to get the original file back.
Is there a size limit?
The practical limit is your browser memory. A feature-length subtitle file is a few hundred kilobytes and is processed instantly.
Will overlapping cues stay overlapping?
Yes. Every time value moves by the same amount, so cues that overlapped before still overlap and the gaps between them stay the same. Nothing is re-timed, merged or reordered.
Can I shift several files at once?
No: this tool handles one file per run so the offset stays under your control. For a batch, apply the same value to each file and verify the first result in your player.
What happens to WebVTT cue settings?
They are read but not written, because the result is plain SRT. If the player needs alignment or position settings, shift first and convert to WebVTT afterwards.