When I work on a book’s design, the first think I think about is the page size. Many times these thoughts reach a rather quick end, as the client has already decided that for me, usually long before I begin. This kind of thing often happens when a publisher wants to continue a long-standing house-style or when the book is one in a series. Smaller publishers may be guided strictly by cost. Page sizes that result in the least waste on the large sheets on which commercial printers print will be the most economical to use. Unusual page sizes will result in higher paper costs.

While the idea of “unusual” page sizes might sound like an interesting line to follow, the truth is that I find the notion of “usual” page sizes to be of far more interest: both what these sizes are, as well as how they became usual.

Currently, in my own work, the size 6 x 9 inches seems to be the page size my clients call for most often. In pursuing the reason why, I found a great book that spoke to the subject, Designing books: practice and theory, by Jost Hochuli and Robin Kinross (London: Hyphen Press, 1996, 2003). The authors make a rather concrete statement, “The following proportions of width to height have proved themselves” and go on to give details.

First, there is the Fibonacci-series proportions. This is a list of numbers that begins with 0 and 1 and continues by adding the last two numbers to get the next one: 0,1,1,2,3,5,8,13,21,34, and so on. The ratios 2:3—this is where 6 x 9 inches comes from—and 5:8 are the two proportions that jump out at me from my own experience. But I doubt the wealth of other proportions would have occurred to me if I did not see the diagram in this book. It displays the following proportions: 1:2, 1:1.732 (the square root of three), 1:1.618 (also called “phi” or “the golden ratio); the “perfect face,” for instance, has this ratio for the following parts—the width of the mouth to the width of the cheek, the width of the nose to the width of the cheek, the width of the nose to the width of the mouth), 1:1.538, 1:1.414 (the square root of 2), 5:9, 3:5, 5:8, 2:3, 3:4.

As to the judgment calls that help me to decide which proportion to use and what specific page size to derive from the proportion I choose, well, I still need to dope those out individually each time I begin a book’s design.