Width of column

What determines the width of a column is design and format however legibility comes first. The reader must be able to read easily and comfortably.

To create a proper width we take in consideration the size of the typeface, the length of the lines, and the leading.
7-10 words per line is recommended.

You want to engage a quality of communication and memorability with your readers which is why we must stick to the 7-10 words per line rule.

“The right width of column is essential for an even and pleasant rhythm of reading which enables the reader to relax and concetrate wholly on the content.”
Josef Müller-Brockmann