In typography, the overall width of a typeset line, usually the area between two margins. Also called measure, column width, or line measure. There are several long-held rules for establishing line length (essentially a function of point size) that ensure maximum legibility. The following chart indicates the recommended line lengths (in points) for a variety of common text point sizes:
Sometimes the formula point size x 2 is used to determine the optimum line length. Lowercase alphabet x 1.5 is also used. For maximum legibility, a line should comprise 55:60 characters, or 9:10 words.
Wider typefaces look best with wider line lengths; condensed faces look best with narrow line lengths. Instead of wide line lengths, double or multiple columns of smaller line lengths should be used.