Subtitle Delay Fixer
Shift all subtitle timestamps forward or backward to sync them with your video. Free, instant, and private — processed in your browser.
How to Fix Out-of-Sync Subtitles
When subtitles consistently appear too early or too late throughout the entire video, it usually means the subtitle file was created for a different copy of the video (a different cut, different language audio, or a file that was re-encoded with a different start offset).
Find the right delay
- Load your subtitle file in a media player alongside the video
- Find a line where you can clearly hear the dialogue
- Measure how many seconds off the subtitle is
- Multiply by 1000 to get milliseconds (e.g. 2.5 seconds = 2500 ms)
- Enter the value above and download the fixed file
Subtitles that drift over time?
If the sync is correct at the start but gets worse toward the end, you have a frame-rate mismatch — not a simple delay. Use the FPS Converter to fix progressive sync drift.
Frequently Asked Questions
Why are my subtitles out of sync?
The most common cause is that the subtitle file was made for a different version of the video — a different cut, dub, or re-encode with a different start offset. A constant delay (same offset throughout) is easy to fix here. If the sync drifts over time, the problem is a frame-rate mismatch — use the FPS Converter.
How do I find the right delay value?
Play the video and note how many seconds a known line of dialogue is off from the subtitle. Multiply by 1000 for milliseconds. If subtitles appear 2 seconds late, enter 2000 ms and shift backward.
Does this work with VTT and ASS files?
The tool parses the SRT timestamp format. VTT files use the same timestamp structure and will work correctly. ASS files use a different format and should first be converted to SRT using a dedicated ASS to SRT tool.