Are my subtitle files uploaded to a server?

No. The file is read, shifted and written back inside your browser. You can disconnect from the internet before dropping the file and it still works.

Does it handle both SRT and WebVTT timestamp syntax?

Yes. SRT uses a comma before the milliseconds (00:00:01,000) while WebVTT uses a dot (00:00:01.000); both are read and written in their own syntax, and hour field or millisecond digits that are missing or over-long are tolerated.

Shift SRT timestamps by a fixed offset

Subtitles that are consistently early or late — after trimming an intro, adding a logo, or a delayed audio track — need one thing: the same offset added to every cue. Drop the file, type the offset, take the file back. Nothing is uploaded.

Drop an .srt / .vtt / .ass file here
or click to choose one · nothing leaves this page

What offset does your situation need?

Symptom	What it is	Typical fix
Every cue is off by the same amount, from the first cue	A fixed edit: trimmed intro/outro, added logo, countdown or channel bumper	One shift, equal to the trimmed length (e.g. `-12.0`)
Audio is late or early against the picture	A fixed audio/video offset introduced by the authoring tool or a re-mux	One shift of that delay (`+0.5` to `+2` seconds is the usual range)
First cues look fine, later cues drift further behind	A frame-rate mismatch, not an offset	Not this page — use the FPS converter
Only the last part is wrong	Two different edits were joined	Split the file, shift each part separately

Rule of thumb: if the error is constant it is an offset (this page); if it grows with time it is a speed/frame-rate difference (the FPS converter).

Timestamp syntax this tool reads and writes

Format	Timestamp shape	Notes
SRT	`00:00:01,250 --> 00:00:04,000`	Comma before milliseconds, cue numbers, blank line between cues
WebVTT	`00:00:01.250 --> 00:00:04.000`	Dot before milliseconds, `WEBVTT` header, no cue numbers required
ASS / SSA	`0:00:01.25`	Centisecond precision, style and position live in the line prefix

Hour field and millisecond digits are normalised on export, so a file that arrives as 0:01,2 leaves as 00:00:01,200.

Doing this to a whole season?

The studio handles batch shifts (apply one offset to every open file), batch ZIP export and CSV/JSON timing reports. Pro is a $9 one-time licence — lifetime, up to 3 devices — with a 7-day refund while the key is unactivated. The free tier keeps every single-file operation on this page, including export.

Open the studio

Questions people ask before using it

How much offset do subtitles usually need?

A fixed offset belongs to a fixed edit: trimming an intro shifts every cue by exactly the trimmed length, and a delayed audio track shifts them all by the same delay. If the drift grows the longer the video plays, that is a frame-rate mismatch — use the FPS converter instead of a shift.

Are my files uploaded?

No. The video file is never involved, and the subtitle file is read, shifted and written back inside your browser. Disconnect from the internet before dropping the file and it keeps working — that is the cheapest way to check.

Can I shift only some cues?

Not on this page — it shifts the whole file, which is what a fixed edit needs. Per-cue editing (select cues, stretch around an anchor) lives in the studio.