Subtitle Sync Tool
Fixes subtitles that get further out of sync as the video plays. Tell it when the first and the last subtitle should appear, and it moves and stretches everything in between to match.
Runs in your browser. Your subtitles are never uploaded.
Sync in four steps
Add the subtitles
Paste them or open the file.
Find the first line
Play the video and note when the first subtitle's words are spoken, like 0:04.2.
Find the last line
Skip to the end and note when the last subtitle's words are spoken, like 1:41:18.
Sync and download
Every subtitle is moved and stretched to fit between those two times.
When to use two-point sync
If subtitles are off by the same amount everywhere, a simple time shift fixes them. If they drift (fine at the start, seconds out by the end), the subtitle file was made for a version of the video that plays at a different speed or has a different length.
Two-point sync fixes both problems at once. It takes the times you give for the first and last subtitles and maps every other time in between proportionally, the same way subtitle editors like Subtitle Edit and Aegisub do it.
Pick lines you can hear clearly. The more accurate the two times are, the better everything in between lines up; a tenth of a second matters. If the video has extra scenes in the middle (a director's cut), no single sync can fix it: split the file at the extra scene and sync each part.
Small details that matter
Shift and stretch
Fixes a delay and a speed difference in one go.
Shows the change
Tells you where the first and last lines moved, and by how much the file was stretched.
Any format
SRT, VTT, ASS, SSA and SBV, saved in the same format.
Frequently
Asked Questions
What's the difference between this and a time shift?
A time shift moves every subtitle by the same amount. Two-point sync also changes the spacing between them, which is what drifting subtitles need.
Which times do I enter?
When the first subtitle should appear and when the last subtitle should appear, both read from the video you're watching.
It's still off in the middle.
The video probably has a scene the subtitles don't (or the other way round). Split the subtitles there and sync each part separately.
Is my file uploaded?
No. It's re-timed in your browser.