Subtitle Time Shifter
Shift SRT and WebVTT subtitle timings by any offset to resync captions with your video.
Drag & drop a .srt or .vtt file here, or click to browse
No uploads. Your files stay on your device.
Paste subtitles above, then set an offset to re-time every cue.
How it works
Paste an SRT or WebVTT subtitle track (or drop the file in), type how many seconds the captions are out by, and every start and end timestamp is re-timed instantly. Use a positive offset when the subtitles appear too early and need to be delayed, and a negative one when they lag behind the dialogue. The quick −1 s / +1 s buttons let you nudge the offset while watching the preview, and the “only shift cues from” field re-times just the tail of a file — handy when an advert break or a missing scene knocked the second half out of sync.
Both subtitle dialects are understood: SubRip’s 00:00:01,000 comma timestamps and
WebVTT’s 00:00:01.000 dot timestamps, with or without an hours field. The output
format selector keeps the original dialect, or converts to the other one — WebVTT output gets
the required WEBVTT header, SubRip output is renumbered from 1 and cue positioning
settings are dropped. Cues that would end up before zero are clamped to
00:00:00,000 and reported.
Everything runs in your browser with plain JavaScript — the subtitle file never leaves your device, so unreleased episodes and client work stay private. Copy the result or download it as a ready-to-use .srt or .vtt file.
Frequently asked questions
How do I shift subtitle timings online?
Paste your SRT or WebVTT track into the box, or drop the .srt/.vtt file onto the drop zone, then type how many seconds to shift by. Every start and end timestamp is re-timed instantly in the preview — use the −1 s and +1 s buttons to nudge the offset until it looks right, then copy the result or download the new subtitle file.
Should I use a positive or a negative offset?
Use a positive offset when the subtitles appear too early: adding, say, 2.5 seconds delays every cue so it lands later. Use a negative offset when the captions lag behind the dialogue. If only the second half of a file drifted — typically after an ad break or a missing scene — put the drift point in the "only shift cues from" field and the earlier cues are left untouched.
Is my subtitle file uploaded anywhere?
No. Parsing, re-timing and the SRT ↔ WebVTT conversion all run in your browser with plain JavaScript, so the file never leaves your device — unlike most online subtitle sites, which upload your track to their server. That makes it safe for unreleased episodes, screeners and client work.