The next step, however, is where things started to get interesting. Not surprisingly, as the font size increased, the average character width also increased. Using text samples like the one in Figure 2, I first calculated the average character width ( c w) at each font size by dividing the resulting line width by the CPL value. Click to enlarge.Īs I stated above, my goal was to determine the mathematical relationship between font size and CPL for particular fonts (obviously, this relationship will differ slightly from font to font). To determine the average character width at a particular font size, you can divide the resulting width (shown in gray next to each line of text) by the CPL. Research sample with Helvetica Neue set to 83 CPL. You can see one of my samples in Figure 2 below.įigure 2. To do this, I examined text samples in the range of 40–100 CPL at font sizes between 5 and 26px for various fonts. Recently, I became obsessed with the idea of predicting CPL at any font size, so I set out to uncover a mathematical relationship between font size and CPL. Problem is, you don’t have a programmatic way to predict CPL…yet. On top of that, it’s simply an imprecise approach, and we all know how I feel about that…Ĭontrary to number one, choice number two sounds great and makes a ton of sense. Figure out a programmatic way to predict CPL, and then choose a width based on this prediction.Ĭhoice number one is a laborious pain in the rear, and it gets old really quickly.

Use the good ol’ trial and error method, whereby you select different widths, count the characters per line, and settle on the width that you prefer.

There are two potential approaches you can take here. So, how can you tune your typography to a specific CPL and, therefore, a specific width? The bottom line here is that your typography should dictate how wide your columns of text are, not vice-versa. Every decision-especially those involving your design and typography-should have a meaningful rationale behind it. They simply pick a column width, and however many CPL that results in…well, that’s what you get.įrankly, I can’t stand this imprecise approach. This has some significant design implications, and worse, most designers don’t even consider CPL when choosing a column width for their text.

Designers must consider this behavior when determining how wide a column of text should be. For a given font size, line width increases as CPL increases.

Alright sans font