Line Breaking and CPS

Note: This section is partially based on the BBC Subtitle Guidelines.

CPS (Characters Per Second)

CPS measures the number of characters, including spaces and punctuation, that appear in subtitles per second.
- Amara

Characters per second is the scale of how readable text is in conjunction with reading speed. It determines whether or not there is enough time to read a certain subtitle line comfortably and without trouble. The simple objective is: low-ish CPS good, high CPS bad.

The CPS column in Aegisub scales from white to red depending on how high it is. Red CPS signifies that it is already dangerously high.

• Always keep it below 20. If it’s higher than that, you should contact your PRs to reword the sentence.
• If your CPS is less than 5, this means the line has a lot of space to work with and you can split and break it down.
• 20 (absolute max 25) if it's a long line (like more than 3 words)
• 15 (absolute max 20) if it's a short line (like 3 words or less)
• Theoretical maximum CPS is 25 and this is for Book Readers.

Line breaking (\N or Shift + Enter)

• An ideal line break will be at a piece of punctuation like a full stop, comma, or dash.
• A line break should always be before a pronoun/name.
• Avoid splitting the following parts of speech:
  • article and noun (e.g. the + table; a + book)
  • preposition and following phrase (e.g. on + the table; in + a way; about + his life)
  • conjunction and following phrase/clause (e.g. and + those books; but + I went there)
  • pronoun and verb (e.g. he + is; they + will come; it + comes)
  • parts of a complex verb (e.g. have + eaten; will + have + been + doing)
• Make sure the line break is justified. This means that the subtitles’ margins should relatively be weighed the same.
  • There are some exceptions to this, such as when a word you’ll be line breaking is too long, you should prefer it to be bottom-heavy.

There should only be 1 line break.

No matter what, there should only be 2 lines stacked on top of each other. If a sentence is too long, break the sentence down and split it into multiple lines instead.

Collabs

If the video has multiple speakers, the maximum lines stacked that should appear is 3.

• If there are only 2 speakers, The one who is the main speaker of the conversation will get a line break while the other does not.
• If 3 speakers are speaking on top of each other, they each only get 1 line. No line breaks.

If there’s more than 3, good luck.