Tool 01 · Timing

Subtitle Sync Shifter

Shift every timestamp in an .srt or .vtt file forward or backward by a fixed amount, so the dialogue lines up with the audio again. Free, instant, no upload limits beyond 5MB.

About this tool

Why subtitles fall out of sync in the first place

A subtitle file that was cut for one release of a video often drifts when it's paired with a different copy of the same file. A few frames trimmed off the intro, a different encode with a slightly different runtime, or a subtitle track pulled from a DVD and reused on a streaming rip are all common causes. The dialogue hasn't moved \u2014 the timestamps in the subtitle file just no longer line up with it.

The fix is almost always the same: apply one constant offset to every cue in the file. That's what this tool does. It reads every timestamp in your uploaded file, adds or subtracts the amount you specify, and rebuilds the file in the same format you uploaded. It doesn't touch the wording, line breaks, or styling of your subtitles \u2014 only the timing.

FAQ

Sync Shifter questions

Play the video and note the timestamp when a line of dialogue is spoken, then compare it to the timestamp shown for that same line in the subtitle file. The difference between the two is your offset.

If subtitles appear before people speak, the track is running ahead and needs to be shifted later (delayed). If subtitles appear after people speak, the track is running behind and needs to be shifted earlier.

Yes. Switch the unit toggle to milliseconds for fine adjustments, which is useful when a track is only a few hundred milliseconds out of sync.

No. A fixed offset corrects a constant delay. If the gap between audio and subtitles grows or shrinks as the video plays, that's usually a frame-rate mismatch, which needs frame-rate conversion rather than a timing shift.