Subtitle Editor

What the editor does

Open a subtitle file and every cue becomes a row: number, start, end and text, all editable in place. The format is read from the content, not the file name, so a renamed SBV or an SRT saved as .txt opens correctly. SubRip (.srt), WebVTT (.vtt), YouTube's SBV and Advanced SubStation Alpha (.ass and .ssa) are supported.

Timecodes accept what people actually type: 00:01:02,500, 1:02.5 or just 62.5 seconds. A value that is not a timecode is marked red and not applied, so a typo never corrupts the file.

• Shift moves every cue, or only the selected ones, by any number of seconds forward or back. A cue that would start before 0:00 is stopped at 0:00 and the page tells you how many were.
• Split cuts a cue where your cursor is, or at the line break or space nearest the middle, and divides its time in proportion to the characters on each side.
• Merge joins two or more cues in a row: the start of the first, the end of the last, the text on separate lines.
• Add, Delete and Undo (the last 60 actions) do what they say.

Timing against your video

Add a video or audio file and it plays right on the page with the current cue drawn over the picture, while the matching row lights up in the list. Click a cue number to jump there; "Start here" and "End here" set the selected cue's times to the playhead. The video is played from your own device and never uploaded — any file your browser can play works, MP4 with H.264 everywhere.

Which checks run, and on what numbers?

Every change is checked at once, and each problem is flagged on its row with a count at the top that jumps to the next one:

• Overlap — a cue starts before the previous one ends. "Fix overlaps" ends each earlier cue where the next begins.
• Ends before it starts — the end time is not after the start time.
• Too fast to read — the cue has more characters per second than the limit you choose: 15, 17, 20 or 25 (17 by default), or off. Characters include spaces but not line breaks or formatting tags.
• Line too long — a line has more characters than your limit: 32, 37 or 42 (42 by default), or off.
• Empty — a cue with no text.

There is no single correct number: subtitle guidelines differ by platform, broadcaster and audience, and are usually stricter for children's content than for adults. Use the limit your client or platform asks for.

Saving and exporting

Your working file is saved in this browser after every change, so a closed tab or a crash does not lose the edits — open the page again and it is back. Nothing is uploaded; the copy lives only in this browser, and "Close file" deletes it.

Download as SRT, as WebVTT, or as plain text with one cue per line. SRT is renumbered from 1 and written with millisecond timecodes. Some things do not survive the trip through the editor: ASS styling and positioning tags and WebVTT cue settings and notes are dropped on import, because SRT has no place for them. Italic tags like <i> are kept as text.