What is
What is Subtitle Timing Shifter & FPS Converter?
Subtitles drift for two reasons: the timecodes start at the wrong moment (offset), or they were authored against a different frame rate than your video file (FPS mismatch). One slips by a constant amount; the other drifts further as the video plays. This tool fixes both at once.
The offset shifts every cue by the same millisecond delta. The FPS converter multiplies every timestamp by a from/to ratio — so a 23.976 fps subtitle file targeted at a 25 fps source gets every timecode multiplied by 0.95904. Apply both together when you need to re-sync after a frame rate conversion, then download in the same format the file came in.
How to use
How to use Subtitle Timing Shifter & FPS Converter
1. Paste or upload your .srt, .ass, or .vtt file — the format is detected automatically.
2. Enter a millisecond offset (negative to make subs appear earlier).
3. If the video frame rate differs from the subtitle source, set From FPS / To FPS or pick a preset (23.976 → 25 etc.).
4. Copy or download the corrected file.
Example
Example
Offset −1500ms applied to:
00:00:05,000 --> 00:00:07,000 Hello
Results in:
00:00:03,500 --> 00:00:05,500 Hello
FPS conversion 23.976 → 25 multiplies every timestamp by 0.95904, so a 10-minute file ends ~24 seconds earlier.Common use cases
Common use cases
1. Re-sync subtitles when the audio starts a few seconds late on a particular release.
2. Match a fansub authored against a 23.976 fps source to a 25 fps PAL transfer.
3. Convert NTSC-to-film telecine subtitles (29.97 → 23.976) when ripping a Blu-ray.
4. Combine offset and FPS shift in one pass to avoid double-rounding error.
Frequently asked questions