When every subtitle appears by the same amount too early or too late, a uniform timeline shift is safer than editing cues one at a time. This tool parses the SRT first, applies one signed offset to every cue, and validates the complete result before enabling download.
Workflow
A short, inspectable path
- 01Choose the SRT file and enter a signed whole-millisecond offset.
- 02Apply the shift; the tool rejects negative starts and revalidates cue chronology.
- 03Download the shifted SRT and spot-check the beginning, middle, and ending cues.
Choose the direction deliberately
Use a positive offset when subtitles appear too early and a negative offset when they appear too late. For example, +1250 moves every start and end time 1.25 seconds later. Cue durations and the gaps between cues remain unchanged.
Distinguish offset from drift
Check at least one cue near the beginning, middle, and end. If the correction is right at the start but wrong later, the problem is drift rather than offset and needs retiming against the actual edit or frame rate.
Local-data boundary
Cue text and timestamps stay on the device. The tool route neither loads a third-party analytics executable nor sends a success, failure, format, or input-size event.
Limits worth keeping visible
- A uniform shift cannot repair drift caused by a different frame rate, a variable edit, or subtitles prepared for another cut of the media.
- An offset that would move the first cue below zero is rejected rather than clamping cues and changing their relative timing.
Reviewed references
- Library of Congress: SubRip Subtitle format description · checked 2026-07-20
- MDN: Using files from web applications · checked 2026-07-20