Book Margins Typical mm

Typical Book Margins (mm)

There is real reasoning behind book margins. Classical layouts borrow their proportions from the page itself, and the version people quote most often is the Van de Graaf canon, where the inner, top, outer and bottom margins sit at 1 : 1 : 2 : 2 (spine : head : outer : foot). When Jan Tschichold redesigned the Penguin Classics he loosened that to roughly 1 : 1 : 1.6 : 1.6, which leaves a comfortable amount of room on the outer and bottom edges for thumbs and scribbled notes.

On a 14 × 21 cm trade book (which lands close to A5), you'll commonly see 15–20 mm at the spine, 15–20 mm at the head, 20–25 mm on the outer edge and 25–30 mm at the foot. The same golden-canon idea shows up in Tschichold’s diagonal construction and in Le Corbusier’s Modulor scale. Both line the diagonal of the text block up with the diagonal of the page, and the result reads as something that simply belongs there rather than something that was fussed over.

Applications

Trade publishers lean on this (Penguin, Companhia das Letras, NYRB), and so do academic presses, anyone self-publishing through KDP/IngramSpark, and PDF book templates. The ratios get borrowed elsewhere too: printed reports, theses (ABNT NBR 14724 allows 30 mm/20 mm) and chapbooks.

FAQ

Why is the inner margin smaller than the outer? Two facing pages share the spine, so the eye reads that whitespace as one combined gap. A wider outer margin then gives the thumb somewhere to sit without covering the text.

Should the bottom margin be larger than the top? Yes. Classical layouts put extra weight at the foot so the block feels visually anchored. Skip it and the text starts to look like it’s sliding off the page.

How much extra for perfect-bound books? On anything over 200 pages, add 3–6 mm to the spine margin (the “gutter”). Without it, the text disappears into the binding.