Fix early or late captions

Subtitle Time Shifter

Enter a positive or negative time adjustment and apply it to every cue. The preview shows the shifted start and end times before download.

Private by default

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Accepted input

SRT, WebVTT, Pasted subtitle text

Available output

Shifted SRT, Shifted WebVTT

Three clear moves

How to use Subtitle Time Shifter

  1. 01

    Open the captions

    Paste or select an SRT or WebVTT subtitle file.

  2. 02

    Set the offset

    Enter how many milliseconds to move cues forward or backward.

  3. 03

    Verify and save

    Review the adjusted timecodes and download the shifted subtitle file.

Good fits

When this tool is useful

  • Delay captions that appear before the spoken audio.
  • Move an entire subtitle track earlier after an edit.
  • Correct a fixed synchronization offset from a media export.

Know before processing

Browser and format limits

  • The same offset is applied to every cue in the file.
  • Cues shifted before zero are clamped to the start of the timeline.
  • The tool does not stretch timing to correct gradual synchronization drift.

Better output

Practical tips

01

Test the beginning, middle, and end of the media after shifting.

02

Use a negative value to move captions earlier and a positive value to move them later.

03

If the offset grows over time, a constant shift will not solve the underlying drift.

Straight answers

Subtitle Time Shifter questions

Should I use a positive or negative offset?

Use a positive value when captions need to appear later and a negative value when they need to appear earlier.

What happens to a cue shifted before zero?

Its time is clamped to the start of the timeline so the output does not contain a negative timestamp.

Can this fix captions that drift farther out of sync?

No. A uniform offset fixes a constant timing difference, not a mismatch that changes across the video.

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