Clean Fonts

Clean fonts: built for the half-second before anyone reads

A road sign, a spreadsheet header and a checkout button all want the same thing from type. The letters have to resolve the instant someone glances at them, in bad light, at an angle, while moving. That's a different job from looking nice in a specimen.

Frutiger had a good way of testing it. Drawing the typeface for Charles de Gaulle airport in 1968, he kept checking letters out of focus, because that's closer to how a traveler sees a sign at speed than any sharp proof is. Whatever shape still held together blurred, he kept. You can do the same thing with any font you're considering.

There's also a nice story in how interchangeable this stuff can be. Vignelli specified Helvetica in his 1970 signage manual for the New York subway, but the transit authority's own sign shop carried on using Akzidenz-Grotesk, probably to avoid buying new equipment. Helvetica didn't actually take over down there until signs got replaced wholesale in the late eighties and nineties. Decades of riders assumed it had been Helvetica the whole time, and nobody noticed the difference.

The families under the label

• Grotesques: plain and businesslike, slightly uneven stroke widths, descended from nineteenth-century sign painting.
• Humanist sans: calligraphic bones under a plain surface, drawn for sustained reading in manuals and long interfaces.
• Softened geometrics: circles and straight lines with the rigidity taken off, so they stay warm at small sizes.
• Screen and system faces: wider counters, taller x-heights, drawn for pixel rendering.
• Big weight ranges: one family covering a whole product, including a few here that run to dozens of weights.

Jobs clean type suits

• Interfaces and dashboards: rows of labels and numbers that need to stay quiet across dozens of screens.
• Corporate identity: type that survives translation into a hundred regional offices.
• Reports and documentation: pages people scan for one number.
• Wayfinding: transit maps, hospital directories, car parks.
• Packaging: products that need to look dependable next to louder competitors.

How to test the font

Shrink it to the smallest size the design will really use, then blur it or step back from the screen. If the word still holds together, it works. If it turns to gray mush, you need a different family, not a heavier weight.

Watch the ambiguous characters. Capital I, lowercase l and the digit 1 are where clean sans faces fall down. You'll only find out when someone can't read a reference number off an invoice. Type "Il1" and look at it.

Leave it plain when it feels too plain. The usual instinct next to a strong client logo is to go heavier or tighten the tracking, and that normally makes things worse. The type isn't there to compete with the identity, it's carrying the label underneath it.