SRT subtitle time shifter
Shift every timestamp in an SRT or VTT subtitle file by a fixed offset.
SRT subtitle time shifter
Subtitles that lag two seconds behind the dialogue ruin a film faster than no subtitles at all. Paste your .srt or .vtt file, type the offset in seconds, and every timing line — HH:MM:SS,mmm --> HH:MM:SS,mmm — moves by exactly that amount. A positive value delays the subtitles (they appear later), a negative one brings them earlier. Decimals work down to the millisecond, so a shift of 0.35 is as valid as a shift of 90.
Only the timing lines change. Cue numbers, the subtitle text itself, WEBVTT headers and cue settings such as align:start survive untouched, and the tool preserves each file's flavor — SRT's comma decimals stay commas, VTT's dots stay dots. Timestamps that would fall below zero are clamped to 00:00:00,000 rather than producing an invalid file, and the tally tells you when that happened.
The common workflow: play the video, note how far off the first line is, paste the file, type that number with the opposite sign of the drift, and copy the result back into a .srt file — or use the download button. Since the tool is line-based it also copes with slightly malformed files: a missing blank line or an odd cue number never stops the shift. Subtitles that start in sync but drift further out as the film runs have a frame-rate mismatch, not a constant lag. Set the source and target rates — 25 to 23.976 for a PAL file against a film transfer — and every timestamp is rescaled by that ratio before the offset is applied. Custom on either side covers a rate that is not in the list.
Everything runs locally in your browser. A subtitle file for an unreleased cut, a client's video or your own home footage never leaves your device — there is no upload, no server-side conversion queue, no waiting.