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🎬 Subtitle Resync

Shift SRT/VTT subtitle timestamps by offset, scale for FPS conversion, and convert between formats.

Time Offset
Positive = later, negative = earlier
FPS Scaling
fps
e.g. 23.976 → 25 for PAL speed-up

About this tool

Subtitle files often drift out of sync with video — a subtitle track ripped from a different release, or subtitles timed for 23.976 fps played against a 25 fps PAL video. This tool fixes both problems: apply a fixed time offset (positive or negative) to shift every cue, and scale timestamps to convert between frame rates.

Example: a subtitle file is 2.5 seconds too early. Set the offset to +2500 ms and every cue moves 2.5 seconds later. Or convert a 23.976 fps subtitle to 25 fps — set the scaling from 23.976 → 25 and all timestamps are adjusted proportionally.

Both SRT (SubRip) and VTT (WebVTT) formats are supported. The tool auto-detects your input format, and you can choose to output in either format — useful when migrating from one format to the other.

FAQ

Why do my subtitles drift out of sync over time?

The most common cause is frame-rate mismatch. A subtitle timed for 23.976 fps played against a 25 fps video will drift by roughly 4% — about 2.4 seconds per minute. Use the FPS scaling (23.976→25) to fix this. A constant offset across all cues usually means the subtitles were extracted from a different release with a different intro or logo.

What is the difference between SRT and VTT?

SRT (SubRip) is the most widely supported subtitle format, using plain text with numeric indices and comma-separated milliseconds. VTT (WebVTT) is the HTML5 standard, using dot-separated milliseconds and supporting optional cue identifiers, CSS styling, and metadata headers. Both store the same timing and text data.

Does negative offset work?

Yes. If your subtitles are too late, enter a negative offset (e.g. -3000 ms). Cues are clamped so start times are never negative — the first cue stays at 00:00:00.000 and later cues shift proportionally.

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