Subtitle Frame Rate Converter
If subtitles start in sync and slowly drift out, they were timed for a different frame rate. Pick the rate they were made for and the rate of your video, and every timestamp is re-calculated.
Runs in your browser. Your subtitles are never uploaded.
Re-time subtitles in three steps
Add the subtitles
Paste them or open the file: SRT, VTT, ASS, SSA or SBV.
Pick both frame rates
"Made for" is the version the subtitles came from; "Convert to" is the video you're watching.
Convert and download
Every start and end time is scaled; the text and formatting stay the same.
Why a frame rate mismatch drifts
Film is shot at 24 fps and released for NTSC players at 23.976 fps. PAL releases play the same film 4.1% faster, at 25 fps. Subtitles timed for one release slip further off the other every minute: over a two-hour film, a 23.976 file ends up almost five minutes late on a 25 fps video.
The fix is to scale every timestamp by the ratio of the two rates, so the subtitle on frame 1,000 stays on frame 1,000. That's what this converter does. 23.976 to 25 is the most common case; 24 to 23.976 causes a smaller drift of about 7 seconds over two hours.
If the subtitles are off by the same amount from start to finish, it isn't a frame rate problem: use the subtitle time shift tool instead. If you don't know either frame rate, the two-point subtitle sync tool fixes drift from two correct times.
Small details that matter
Every common rate
23.976, 24, 25, 29.97, 30, 50, 59.94 and 60 fps.
Formatting kept
Italics, line breaks and ASS styles come through unchanged.
Same format out
An SRT comes back as an SRT, a VTT as a VTT.
Frequently
Asked Questions
How do I know which frame rate my subtitles were made for?
Releases from PAL countries (most of Europe) are usually 25 fps; Blu-ray and streaming films are 23.976 fps. If the subtitles end up late on your video, they were made for a slower rate than the video; if early, a faster one.
My subtitles are off by the same amount the whole way through.
That's a delay, not a frame rate mismatch. Use the subtitle time shift tool and enter the offset in seconds.
Does this change the video?
No. Only the subtitle file's timestamps change.
Is my file uploaded?
No. The conversion runs in your browser.