Foolscap folio

Foolscap folio (commonly contracted to "foolscap" or "folio") is paper cut to the size of 8½ × 13½ inches (216 × 343 mm). This was a traditional paper size used in Europe and the Commonwealth, before the adoption of modern international paper A4 paper (the most common standard size outside the United States). It is a common size for ring binders/lever arch files containing A4 paper because it offers greater protection to the edge of the pages than an A4 binder, as foolscap size is larger than A4 paper size. A full "foolscap" paper sheet is 17 x 13½ inches (432 × 343 mm) in size, and a "folio" sheet of any type is simply half the standard sheet size.

Foolscap was named after the fool's cap and bells watermark commonly used from the fifteenth century onwards on paper measuring 17 × 13½ inches (432 × 343 mm) or a subdivision of this into halves, quarters and so on. The earliest example of such paper that is firmly dated was made in Germany in 1479.

Unsubstantiated anecdotes suggest that this watermark was introduced to England in 1580 by Sir John Spielmann, a German who established a papermill at Dartford, Kent. Apocryphally, the Rump Parliament substituted a fool's cap for the royal arms as a watermark on the paper used for the journals of parliament.

In Brazil the 8½ × 13 inches paper size is usually named "Folio", and it is also sometimes called "Ofício II", a reference to the 8½ × 14 inches (216 × 356 mm) paper size (which is named "Legal" but in Portuguese is better known as "Ofício").

See also

F4 (paper) - this is sometimes called foolscap even though the dimensions are not usually 8½ × 13½ inches.