How to edit SRT subtitles

Subtitles that run ahead of the speech, or a typo in cue forty. Both are quick to fix once the file is open.

An SRT file is a numbered list of cues, each with a start time, an end time and some text. Editing is mostly a matter of adjusting those three things.

Step-by-step

1. Load your .srt.
2. Edit text or timings cue by cue.
3. Or shift everything by a fixed offset.
4. Save.

The two kinds of sync problem

Constant offset. Subtitles are consistently two seconds early throughout. One shift of the whole file fixes it. This is by far the commoner case, usually caused by a different version of the video with a longer intro.

Drift. Subtitles start correct and gradually fall behind. This means the frame rates differ, and shifting will not help — the error grows through the file. It needs the timings scaled rather than moved.

Diagnose before you start: check sync at the beginning and again at the end. If the error is the same at both, shift. If it has grown, you have drift.

Readable subtitle timing

• At least a second on screen, even for two words.
• No more than about seven seconds for a single cue.
• Two lines maximum, around forty characters each.
• Break lines at natural pauses, not mid-phrase.

Frequently asked questions

My subtitles drift further out as the video goes on. Can shifting fix it?

No. Drift means the frame rates differ, so the error grows with time. The timings need scaling rather than moving by a constant.

How long should a subtitle stay on screen?

At least a second, and rarely more than about seven. Two lines of roughly forty characters is the usual maximum for comfortable reading.

Is my file uploaded?

No. It is opened and saved in your browser.