Folio is a realist sans-serif typeface designed by Konrad Bauer and Walter Baum in 1957 for the Bauersche Gießerei (in English: Bauer foundry). Bauer licensed the design to Fonderie Typographique Francaise for sale in France under the name Caravelle.

Like Helvetica and Univers, which were also released at the same time, it is part of the International Typographic Style and modeled after Akzidenz-Grotesk. However, Folio is more closely modeled on Akzidenz-Grotesk than the other two, which have larger x-heights. Due to good marketing, the typeface experienced moderate success in the United States. The typeface family was extended in 1963, adding an Extra Bold weight and a Bold Condensed width.

Some distinguishing features of the typeface are the capital Q's tail is centered under the figure, the uppercase J has a slight hook, and there are two versions of uppercase R, one with a straight tail and one with a curved tail.

Folio is a trademark of Bauer Types registered in the US Patent and Trademark Office and may be registered in other jurisdictions.