Subtitle Line Breaker

The Subtitle Line Breaker re-wraps every cue in a SubRip file so no display line exceeds your limit. Paste the subtitles into the SRT Content box, set Max characters per line, and the tool returns a complete SRT - downloadable as an .srt file - with unchanged timings and text broken at word boundaries into readable lines.

Overlong lines are the signature of a translated file, a transcript pasted from a document, or a merge that flattened two-line captions into one. They overflow the safe area, clip on phones and force viewers to read faster than they can. Subtitlers working to broadcast style guides, vendors whose target language ran 30 percent longer, and accessibility teams preparing compliant captions all need bulk re-wrapping.

The algorithm is conservative. Cue text is split on the breaks it already has, and any line already within the limit passes through untouched. A long line is split on spaces and rebuilt greedily: words are appended until the next would exceed the limit. Nothing is hyphenated and no word is ever cut, so a single token longer than the limit stays intact on its own line. Numbering and both timecodes are carried through unchanged.

All wrapping happens in your browser with no upload, and full-length files finish instantly.

• Max characters per line control: Set the limit that matches your delivery spec - 42 is the common broadcast maximum - and leave the field empty to fall back to 42 automatically.
• Word-boundary breaking: Lines are split only at spaces, so no word is ever cut in half and no hyphen is invented, keeping the text exactly as written.
• Existing breaks respected: The cue is split on its current line breaks first, and any line already inside the limit is emitted unchanged, so deliberate two-line phrasing survives the pass.
• Greedy fill for compact output: Each new line is packed with as many whole words as fit, which keeps the number of display lines to the minimum the limit allows.
• Long single words left whole: A token longer than the limit, such as a URL or a long proper noun, is kept intact on its own line rather than broken, which is the safe behaviour for readability.
• Timings and order untouched: Start and end timecodes come through exactly as parsed and cues stay in sequence, so wrapping can never desync the file.
• Whole-file pass: Every cue in the pasted SRT is processed in one run, so a feature-length track is normalised in a single click.
• Browser-only and private: The subtitle text is never sent to a server, which makes the tool usable on client and pre-release material.

1. Click Load sample to fill the SRT Content box with an example file if you want to preview how the wrapping behaves.
2. Paste your own subtitle file into the SRT Content box, complete with cue numbers and timing lines.
3. Set Max characters per line to your target, typically 42, or lower it to 37 or 40 if your client style guide is stricter.
4. Press Run to re-wrap every cue; the rebuilt SRT appears in the output panel.
5. Review the result and check that no caption now runs to three or more lines - if it does, the dialogue itself is too long for the cue duration and needs condensing rather than wrapping.
6. Click Copy for the clipboard or Download to save the file as .srt.
7. Run the Line Length Checker at the same limit afterwards to confirm the file now reports no long lines.

Example 1 - flattened translation re-wrapped at 42. A translated cue arrived as one 68-character line.

Before:
4
00:00:21,300 --> 00:00:25,000
The committee will publish its findings before the end of the month.

After:
4
00:00:21,300 --> 00:00:25,000
The committee will publish its findings
before the end of the month.

The break lands between whole words, both lines sit under 42 characters, and the timecodes are identical, so nothing about the sync changes.

Example 2 - a word longer than the limit. With the limit at 20, a cue containing Kraftfahrzeughaftpflichtversicherung keeps that word on a line of its own instead of being chopped mid-word, because the wrapper only ever breaks at spaces.

• Compliant deliveries without hand editing: A whole file is brought inside the character-per-line rule in one pass, so you meet broadcaster and platform specs without touching each cue.
• Captions that read in the time available: Two balanced lines are far quicker to absorb than one long run of text, which directly improves comprehension for fast dialogue.
• No clipping on mobile: Wrapped text stays inside the safe area on phones and tablets, where over-long lines are otherwise truncated or shrunk.
• Text integrity preserved: Because words are never split and no hyphens are added, the wrapped file still reads exactly as the translator or transcriber wrote it.
• Sync is never at risk: Only the text changes, so you can re-wrap late in the process without re-checking timing against the picture.
• Private handling of client files: Wrapping happens in the browser, so unreleased episodes and confidential training material never leave your machine.