F4 is a paper format of size 210 mm x 330 mm[1]. Although metric, based on the A4 paper size, and named to suggest that it is part of the official ISO 216 paper sizes, it appears to be only a de-facto standard. It may be referred to as "foolscap" or "folio" because of its similarity to the traditional Foolscap Folio size of 8½ × 13½ inches (216 mm x 343 mm).
See also
- Paper size
- ISO 216 - International standard of paper sizes
