4to stands for quarto, a traditional book format where a full sheet of paper is folded twice to create four leaves or eight pages. This yields a roughly squarish, medium-large volume commonly used for art books, manuals, and older editions. Binders and catalogers use this notation to quickly communicate the physical dimensions and folding scheme of a volume.
Heard on the job
The client wants the exhibition catalog done as a 4to to give the photographs more breathing room on the page.
Insider tip
While 4to technically refers to the folding method, booksellers often use it loosely to describe any book roughly 9 to 12 inches tall.
Also heard as
- quarto