The Typographic Measure: Mastering Optimal Line Length
A pervasive error in typographic implementation occurs when designers subordinate readability to layout constraints—prioritizing visual symmetry over the fundamental cognitive processes that govern effective reading comprehension.
This misalignment of priorities frequently manifests as excessive line length, a seemingly innocuous decision that significantly impedes the reader's ability to efficiently process textual information.
To cultivate optimal reading conditions, constrain paragraph width to accommodate between 45 and 75 characters per line—a range established through extensive research in cognitive psychology and reading behavior. In digital environments, this constraint is most elegantly implemented through em units, which establish a proportional relationship with the current typographic scale. A dimensional constraint of 20-35em typically yields the ideal character count within this cognitive sweet spot.