What is the recommended range for line length in readable print materials, and why does it matter?

• A. About 60-90 characters per line, which maximizes text density.
• B. About 50–70 characters per line; this range supports efficient tracking and reduces eye fatigue.
• C. About 20-30 characters per line; this minimizes scrolling.
• D. Line length is irrelevant to readability.

Answer: (B)

Line length determines how easily the eyes move from the end of one line to the start of the next. About 50–70 characters per line hits a sweet spot where a reader can track lines without making long, tiring eye jumps or being forced to read too many short, choppy lines. With this range, you typically get about 9–14 words per line, depending on word length, which keeps the rhythm of reading steady and reduces fatigue.

If lines are much longer, the eye has to travel farther, which can cause losing one’s place and slow reading. If lines are too short, the text breaks up frequently, creating disruptive pauses that interrupt flow and comprehension. The 50–70 character range balances these factors, supporting smoother reading, faster scanning, and better comfort over longer passages.

The other options either push line length toward overly dense text, which increases eye strain, or toward too-short lines, which interrupts the reading rhythm. Saying line length is irrelevant contradicts a well-established finding in readability studies.