Fix Subtitle Sync

Out-of-sync subtitles, fixed with one number

Subtitles a second or two off make a video tiring to watch. It usually happens because the video has a different intro length or frame rate than the release the subtitles were made for. This tool shifts SRT or VTT timings by any amount, or stretches subtitles that drift further off over time, and shows before/after times so you can check.

Shift all

If the offset is the same from start to finish, use this. Subtitles appear after the speech → choose “Earlier”; before the speech → “Later”. Enter seconds in 0.1-second steps (e.g. 2.3). If only part of the video is off (say, after a cut scene), enter the subtitle number to start from and earlier lines stay put. Tip: find the right value with your video player's subtitle delay setting, then enter it here.

Match two points

If subtitles start in sync but drift apart, it's a frame-rate difference (for example 23.976 vs 25 fps). Watch the video and enter when the first and last lines are actually spoken. Every subtitle in between is stretched or squeezed by the same ratio. Use the format 00:01:02,500.

Formats

SRT is used by most players; VTT by web players and YouTube. You can convert between them when saving. The file's encoding is detected automatically, and output is UTF-8. SMI subtitles aren't supported. To get just the text, use Subtitles to Text. Files never leave your device.