Subtitle Sync
Fix subtitles that appear too early, too late or progressively drift away from the dialogue.
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How to use Subtitle Sync
- Paste UTF-8 SRT or VTT text, or open a subtitle file up to 2 MB. No video upload is needed.
- Use a positive shift to show every cue later or a negative shift to show it earlier. For gradual drift, enter two old and correct times in seconds.
- Review the output and download it in its original format. Load it with your video and check both ends of the recording.
When this helps
A constant delay needs one shift. A timing difference that grows over the recording needs two corresponding anchors. Choose spoken lines far apart for a more useful correction.
What to know before you start
This is a manual timing tool, not automatic speech recognition. It keeps text and VTT settings. An adjustment that creates negative timestamps is rejected instead of deleting cues. Supports up to 10,000 cues.
Frequently asked questions
What is the difference between delay and drift?
A delay is a constant offset. Drift grows over time; the two-anchor mode applies a linear time stretch and offset.
Will formatting survive?
The sync tool preserves subtitle text, cue identifiers, VTT settings and metadata while rewriting timestamps. Line endings are normalized.
What if a cue would move before zero?
The tool stops and explains the problem. Use a smaller negative shift or edit the source; cues are not silently dropped.