book size

Definition

Size of a closed-book lying flat on its face or back, measured from head to tail and from spine to fore edges of the cover. There is no standard method of naming book sizes, and there is little or no consistency in the dimensions of a named-size. The book sizes (in inches) as classified by the American Library association are: (1) Folio 12 x 19, (2) Quarto 9½ x 12, (3) Octavo 6 x 9, (a) Imperial octavo 8¼ x 11½, (b) Super octavo 7 x 11, (c) Royal octavo 6½ x 10, (d) Medium octavo 6? x 9¼, (e) Crown octavo 5? x 8, (4) Duodecimo 5 x 7?, (5) Duodecimo large 5½ x 7½, (6) Sextodecimo 4 x 6¾, (7) Octodecimo 4 x 6½, (8) Trigesimo-segundo 3½ x 5½, (9) Quadrasegisimo-octavo 2½ x 4, (10) Sexagesimo-quarto 2 x 3.