Subtitle Timing Shifter (Sync Subtitles)
Fix out-of-sync subtitles — shift every SRT or VTT timestamp earlier or later by any number of seconds, or stretch timing to fix drift.
How to use
- 1Paste the SRT or VTT file.
- 2Enter how many seconds to shift (negative = earlier). Use 'Speed factor' if subtitles drift more over time.
How it's calculated
New time = old time × factor + shift. A 23.976 → 25 fps mismatch needs a factor of 23.976 ÷ 25 = 0.959.
Frequently asked questions
Subtitles appear too early — which way do I shift?
Enter a positive number to delay them. If they appear too late, use a negative number.
They start in sync but drift apart — what now?
That's a frame-rate mismatch. Try a factor of 0.959 (subtitles made for 23.976 fps on a 25 fps video) or 1.0427 for the reverse.
Is the format kept?
Yes — SRT stays SRT and VTT stays VTT. Cues that would start before 0:00 are clamped to 0.