Line Break & Reading Speed Reflow
Rebalance over-long subtitle lines at natural phrasing pauses, keep every line inside the character limit, and see which cues are simply too fast to read. Timings and cue order are never changed.
These are the same presets the validator checks against, so a cue that is reported as too long here is the same cue it would report.
Drop your SRT or WebVTT file to rebalance its lines
Line breaks only. Timecodes and cue order stay exactly as they are
Why 42 Characters and Two Lines
A subtitle line is not a paragraph. At a typical viewing distance a viewer can take in roughly 37 to 42 latin characters in one glance, and two lines is the most that can be read without covering the picture. Beyond that the viewer starts reading instead of watching, which is the failure the numbers exist to prevent. Reading speed is the second half of the same idea: characters divided by how long the cue is on screen, with about 21 characters per second as the working ceiling for web video.
The harbour at dawn was quieter than the director had promised it would be.
The harbour at dawn was quieter than the director had promised.
What This Tool Changes, and What It Refuses To
- Changes: where the line breaks fall inside cue text, so each line fits the character limit and the two lines are roughly even.
- Changes: nothing else. Times, order, numbering and every cue that already fits are re-emitted exactly as they were read.
- Refuses: to split one cue into two, or to merge cues. Both change when dialogue appears on screen, which is a timing decision rather than a layout one.
- Refuses: to claim a fast cue is fixed. Reading speed is unaffected by line breaks, so those cues are listed for you instead.
Why the Breaks Look Deliberate
The break points are chosen by comparing every legal layout and scoring them on how even the lines are and whether the break lands after punctuation. That is why a sentence boundary wins when it fits, and why a two-line cue does not end with a single stranded word. A greedy fill to the limit would be simpler and would produce exactly those two defects, which are the ones viewers notice.
Frequently Asked Questions
- Will reflowing change my timecodes or cue numbers?
- No. Only the line breaks inside cue text move. Start and end times, cue order and cue numbers are re-emitted exactly as they were read, and no cue is split into two or merged with another.
- What happens to cues that are already fine?
- They are left completely untouched, including deliberate line breaks you set yourself. A reflow that rewrites every cue is indistinguishable from one that damages every cue, so this tool only reports and rebalances cues that actually break a limit.
- My line is too long but the text cannot fit two lines. What then?
- The tool says so instead of forcing a break. It shows the best available layout and reports the cue separately, because at that point the dialogue itself has to be shortened. Forcing the break would hide the problem rather than fix it.
- Does this fix a cue that is simply too fast to read?
- No, and nothing that only moves line breaks can. Reading speed is characters divided by how long the cue is on screen, so it changes only when the wording gets shorter or the cue stays up longer. Cues over the limit are reported so you can fix them in your editor or subtitle tool.
- Are my subtitles uploaded anywhere?
- No. The file is parsed and reflowed in your browser. There is no upload and no account, the same promise every tool on this site keeps.