The best page size

Well, I’ve delayed long enough on this one. It starts out “If 8.5" x 11" paper weren’t the best paper size for reading, it wouldn’t be the standard size for office documents.” I wish it were so obvious. In fact, if you are in Europe, you might be saying the same thing for A4 size paper (210mm x 297mm). So this is my opportunity to talk a little history about paper.

First off, understand that printing (or even writing) on pages is a relatively new technology. For thousands of years people rolled their words up in scrolls for which the size of the sheet was as big as you need. It’s not unlike the bottomless pages of the internet that scroll down until you run out of content.

Some of the first books bound together out of separate leaves of paper appeared in the 13th and 14th centuries. These were so significant in their difference from scrolls that they often bore the name “codex” meaning a paginated document. When the printing press came along in Europe in the middle of the 15th century, it was much easier to print on separate sheets than on long scrolls, so paginated content became the norm. To do massive runs of printed material it was necessary to have a standardized page size in an era where everything was being made by hand.

But what size?

Enter animal nature. Paper-making was still in its infancy in Europe, though it had been around for hundreds of years in Asia. Far more reliable were animal skins, specifically calfskin which was treated, scraped thin or even split, and dried to form a suitable writing or printing surface. The standardized paper size seems to be derived from the largest dependable size rectangle that could be cut out of the hide of a calf. This rectangle is approximately 24" x 34", from which two 24" x 17" sheets of printing stock, or “folios” could be cut. After gathering the folios into quires, binding them together and trimming them, the final trim size for a large book was about 11" x 17" or twice a letter size sheet of paper. It was far too costly to do extensive print runs on vellum, however, and the art of making paper was quickly advanced as the medium for printing. Paper, which could have been moulded into any desired size, seems to have evolved to reflect the dimensions of the calfskin.

So, 8.5" x 11" paper is not that size because it is desirable, but because it is an artifact of how fat a calf of butcherable size is.

Enter the philosophy of the Golden Rectangle. Many philosophers held that there was a divine proportion that was reflected in works that were most pleasing to the eye. Exactly how to compute this perfect mean, however, was a matter of dispute that has never been precisely resolved. Based on the work of da Vinci and Fibonacci who looked at the proportions of Greek temples, etc. the mystic proportion was deemed to be approximately 1:1.618. This can be constructed by creating a number string beginning with 0,1 and having each number continuing the string be the sum of the previous two. So the string goes: 0,1,1,2,3,5,8,13,21,34,55,89.... As you compare each consecutive pair of numbers you discover them getting ever closer to 1.6181 without actually reaching it. One pair will be slightly below and the next slightly above. These held that this string of numbers revealed the divine proportion and that a perfectly sized sheet of paper would have this proportion. Indeed, some newspapers today still have the proportion in broadsheet of 1:1.618. (Letter size, by the way happens to be 1:1.294, quite a way from the divine.)

The Bauhaus design movement of the early 20th century, inspired in part by the work of Swiss architect LeCorbusier charted a slightly different relationship as that of the side of a square to its diagonal. This is approximately 1:1.414. This relationship has the great advantage of being proportionally stable when folded in half. Taking a sheet of paper with a surface area of 1 square meter in dimensions proportionate to 1:1.414, you can fold it down until it reaches as size of 210mm x 297mm and it will still have a width to height ratio of 1:1.414. Hence we get the A series of papers and A4, now commonly in use in most of the metric world.

Many other sizes have been promoted as being the idea reading size with more or less success. My personal philosophy is that the perfect reading size for the page is proportionate to the amount of type that you are putting on it because, frankly, people don’t read the page, they read the type. We can determine an appropriate width of a line of type as discussed in the post on Optimum Line Length below. Determining the right height of a column of text or a page of text is something that we will have to leave up to individual aesthetics and physical circumstances.