Fix subtitles that are out of sync.
Out-of-sync captions have three different causes, and only one of them is fixed by moving every timestamp. Measure two points in the video first, then choose the correction that matches what you measured.
Last updated September 17, 2026
Measure before you change anything
Pick a clearly spoken word near the start of the video and another near the end. For each, note when you hear it and when its caption appears. Write both differences down with a sign: if the caption appears after the word, it is late; if it appears before, it is early. Two measurements are the minimum, because one number cannot tell a constant offset from drift. Add a third in the middle when the video is long or has been re-edited.
Constant offset: every caption is off by the same amount
If the caption at 00:00:12 is 1.5 seconds late and the caption at 00:38:40 is also 1.5 seconds late, every cue needs the same correction. This usually happens when an intro, a countdown or a few seconds of silence were trimmed or added after the subtitles were made. It is the only case one global shift solves. Use the subtitle timing shifter with the measured difference.
Getting the sign of the shift right
Enter the correction, not the error. Captions that appear late need a negative offset to make them appear earlier: 1.5 seconds late means -1.5. Captions that appear early need a positive offset to delay them: 0.8 seconds early means +0.8. The shifter moves the start and end of every cue by the same amount, so each caption stays on screen for as long as before. After a negative shift, any cue that would now end at or before 00:00:00 is removed, and a cue that crosses zero starts at zero.
Progressive drift: the gap keeps growing
If captions are 0.2 seconds late at one minute and 3.1 seconds late at forty minutes, the timing is stretched, not shifted. Common causes are subtitles made for a copy at a different frame rate or playback speed. No constant shift can fix drift: move the file to match the start and the end gets worse, match the end and the start breaks. It needs a tool that rescales timing between two sync points, or captions generated again against the exact video you are publishing. The timing shifter here does not rescale or convert frame rates.
A different edit: in sync, then suddenly off
If the first half is fine and everything after one scene is out by the same few seconds, the video was edited: a section was added, removed or reordered. A single shift fixes one half and breaks the other. Correct the cues after the change separately in a subtitle editor that can shift a selected range, or generate captions from the edited video. When several sections have moved, generating again is usually faster than repairing.
Isolated cues: a few captions are wrong, the rest are fine
Sometimes the file is in sync except for a handful of cues — often around fast exchanges, music or a long pause. Change only those timestamps. In a plain SRT or VTT file that means editing the timing lines in a text editor; in SRT vs VTT you can see which timestamp syntax each format expects. If the captions were generated in this product's editor, switch to Advanced mode and drag the caption's edges on the timeline instead of shifting the whole file.
Check the result where it will be watched
Re-measure the same two or three points after the correction, then play the file in the destination player. Some players add their own subtitle delay setting, which can make a correct file look wrong. If you are starting from a video with no usable subtitle file, add subtitles to the video directly so the timing is created from that exact footage.
Which fix matches what you measured
| What you see | Likely cause | What to do |
|---|---|---|
| Same error at the start, middle and end | Constant offset | Shift every cue by the opposite of the error in the timing shifter |
| Small error at the start, larger error later | Progressive drift from a frame-rate or speed difference | Rescale between two sync points in software that supports it, or generate captions for this video |
| Correct until one point, then off by a fixed amount | A different edit of the video | Correct the later range separately, or generate captions from the edited video |
| A few captions wrong, everything else correct | Isolated incorrect cues | Edit only those timestamps by hand or on the editor timeline |
Before: every cue is 1.5 seconds late
The words are heard at 00:00:10.500 and 00:00:13.700, but the captions appear at 12.000 and 15.200.
1
00:00:12,000 --> 00:00:14,800
Thanks for staying to the end.
2
00:00:15,200 --> 00:00:17,400
The checklist is linked below.After: shifted by -1.5 seconds
Both cues move 1.5 seconds earlier and keep their original durations of 2.8 and 2.2 seconds.
1
00:00:10,500 --> 00:00:13,300
Thanks for staying to the end.
2
00:00:13,700 --> 00:00:15,900
The checklist is linked below.Drift: why one shift is not enough
Measured lateness grows through the video. Shifting by -0.2 fixes the first line and leaves the last 2.9 seconds late; shifting by -3.1 makes the first line appear 2.9 seconds early.
Heard at Caption at Error
00:01:00.0 00:01:00.2 +0.2 s late
00:20:00.0 00:20:01.6 +1.6 s late
00:40:00.0 00:40:03.1 +3.1 s lateFrequently asked questions
Should I enter a positive or negative number?+
Enter the opposite of the error. Captions that are late need a negative offset to move earlier; captions that are early need a positive offset to be delayed.
Can a timing shift fix subtitles that get worse over time?+
No. That is drift, and shifting everything by one amount only moves the point where the captions line up. It needs rescaling between two sync points or captions made for the exact video.
Does the timing shifter convert frame rates or re-align automatically?+
No. It moves every cue by one offset you choose. It does not listen to the audio, detect drift, change frame rates or retime individual cues.
Why did some captions disappear after a negative shift?+
A cue that would end at or before the start of the video can never be shown, so it is removed. A cue that only starts before zero is kept and starts at zero.
Is it faster to fix the file or generate new captions?+
For a constant offset, fixing the file takes seconds. For drift or a video that has been re-edited in several places, generating captions from the final video is usually quicker and more reliable.