The ideal measure for single column of text is most widely accepted as around 65 characters, but does this depend on the language of the text? Some languages like French have much longer words than English (on average), and thus can fit less words per line. This can be thought of as less information per single line of text.
Well, it’s absolute in my head any way 😉
A readable text finds the right measure based on three main variables:
- Type face (and accompanying spacing preferences)
- Type size
Those variables are going to dictate how much room your text needs to properly set up a line.
If the language or type of writing* you’re dealing with averages more characters per word it’s going to need a longer line to avoid
- Big gaps in justified text
- Erratic line ends in flush left
- Excessive hyphens
It may not be a big difference, but it should be a factor in the measure to some extent.
This factor will become less and less critical as your measure increases. If you’re working at the far end of the comfortable reading spectrum (say 70 to 80 characters) there is much more room for variance in the word size.
* Academic or technical texts are notorious for their use of long words that are otherwise uncommon in a language.