A tour of the level of detail that goes into Hoefler & Frere-Jones' fonts.

In the middle of Gotham, our family of 66 sans serifs, there is a hushed but surprising moment: a fraction whose numerator has a serif. So important was this detail that we decided to offer it as an option for all the other fractions, a decision that ultimately required more than 400 new drawings. Why?

As you'll read below, it's something that we added because we felt it mattered. Even if it helped only a small number of designers solve a subtle and esoteric problem, we couldn't rest knowing that an unsettling typographic moment might otherwise lie in wait. We've always believed that a good typeface is the product of thousands of decisions like these, so we invite you to join us on a behind-the-scenes look at some of the invisible details that go into every font from H&FJ.

Aspirational.

Responding to a query from an NPR science correspondant about prime numbers, Hoefler & Frere-Jones researched the lengths involved when typesetting the largest known prime number, which has almost 13 million digits.

Joe liked the idea of measuring how long this number would be if it were set in type, which immediately called into question the choice of font. The number's length would depend chiefly on the width of the font selected, and even listener-friendly choices like Times Roman and Helvetica would produce dramatically different outcomes. Small eccentricities in the design of a particular number, such as Times Roman's inexplicably scrawny figure one, would have huge consequences when multiplied out to this length. But even this isn't the hairy part. Where things get difficult, as always, is in the kerning.

In some cases, properly kerning the number resulted in a difference of more than 1000 feet for 12 pt. text.

New web site for Hoefler & Frere-Jones, the noted and celebrated typeface designers, including a weblog. Subscribed. Oh, and the browser fonts of choice for the meticulous duo? "Lucida Grande, Lucida Sans, Verdana, Georgia, Helvetica, Arial" (thx, jonathan)