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How to shift subtitle timing on a Mac
By Himanshu Ranjan · Updated 8 November 2026
Select the subtitle file in Finder, open FileDial, and run Edit › Shift timing… Enter how far to move every cue, using a negative amount to show subtitles earlier. It saves a new copy and works offline. It fixes a constant offset, not drift that grows through the film.
Two kinds of out of sync
Subtitles can be wrong in two different ways. A constant offset means every line is early or late by the same amount, for example because the video has a few seconds of intro the subtitles were not made for. A shifting offset means the error grows as the video plays, usually because the subtitle was timed for a different frame rate or an edited cut.
A shift tool fixes only the first kind. To work out which you have, check a line near the start and one near the end. If both are off by the same amount, shift. If the end is off by much more, shifting will not fix it.
Shift the timing with FileDial
- Play the video and find a line near the start. Note how many seconds early or late it appears.
- Select the subtitle file (SRT or VTT) in Finder.
- Hold the right Option key to open the dial.
- Choose Edit › Shift timing… and enter the amount. A negative value moves subtitles earlier.
- Play the video with the new file and check the start and the end.
How to measure the offset
Pick a line with a clear start, such as a loud first word. Compare when it appears on screen with when it is spoken. If subtitles show half a second late, shift by minus half a second. Make a note of the first and last lines and test both after shifting. Small fixes are best made in small steps, rechecking each time.
Keep the original
FileDial saves a new copy, so the original subtitle file is untouched and you can try again with a different amount. If you make several attempts, you will end up with several copies. Use Rename › Rename with pattern… to give them clear names, or delete the failed attempts.
After shifting
If you then need a different format, use Convert › Convert to SRT or Convert › Convert to WebVTT. To attach the fixed file, Combine › Add subtitle track adds it as a switchable track with no re-encoding, or Combine › Burn in subtitles makes it permanent. The subtitles guide covers both.
Why constant offsets happen
The usual causes are a video with a different intro than the one the subtitles were timed against, such as a studio logo, a recut that removed a few seconds from the start, or subtitles prepared for a different release of the same film. In all of these the whole file is early or late by the same amount, and a single shift fixes it.
Drift has different causes: a different frame rate between the subtitle source and your video, or scenes cut from the middle. If a line near the start is correct but the last line is several seconds off, a fixed shift cannot help, and the right fix is subtitles made for your release.
A careful way to find the amount
Choose a line about a minute in, rather than the very first, because the first line is often the least reliable. Play the video to that spot and note the difference between speech and text to the nearest half second. Apply that shift, then check the first line, one in the middle and one near the end. If all three are right, you are done. If the error changes between them, you are looking at drift.
Remember the sign. FileDial's note says a negative amount moves subtitles earlier, so if the text appears after the speech, use a negative value. If it appears before the speech, use a positive one.
Mistakes and alternatives
The common mistakes are shifting in the wrong direction, shifting by a big number to compensate for drift, and overwriting the only good copy. FileDial avoids the last one by saving a new file, but you can still lose track of which attempt is best, so name them.
Many video players, including some on the Mac, have their own subtitle delay setting, which fixes the problem for viewing without changing the file. That is the quickest check for the right amount: adjust the player until it looks right, note the number, then apply it with Edit › Shift timing… so the fix travels with the file.
Offline
Subtitles for unreleased material should not need an upload. FileDial runs every tool on your Mac and never uploads a file, and all tools work with Wi-Fi off.
Questions
How do I make subtitles appear earlier?
Run Edit › Shift timing… in FileDial and enter a negative amount, since negative moves subtitles earlier. Positive values show them later. The result is saved as a new copy and the original is untouched. Negative values are the part people forget, so test with a small amount and play the video to confirm the direction.
Why do my subtitles drift out of sync over time?
The subtitle was probably timed for a different frame rate or a different cut of the video. A fixed shift cannot fix that. You need subtitles that match your version of the video. A fixed shift only suits a constant offset, so check both ends of the video before deciding which problem you have.
Does shifting work on VTT as well as SRT?
FileDial lists the tool for subtitle files in general. Select an SRT or VTT in Finder and run Edit › Shift timing… Check the result in your player. If a player supports subtitle delay, use it to find the right number, then apply that amount to the file permanently.
Can I shift many subtitle files at once?
Yes, select several files and run the tool once. The amount you enter is applied to each file in that run, so only batch files that share the same offset. Only batch files that share one offset, such as episodes from the same release, because the same amount is applied to each.