What are the margins and gutter for a KDP puzzle book?
Updated 14 September 2026
Keep at least a 0.25 inch outside margin (more is safer for puzzles), and set the inside gutter by page count: about 0.375 inch up to 150 pages, 0.5 inch from 151 to 300 pages, and larger above that.
The gutter margin is the inside margin nearest the spine, and it must grow with page count so the binding does not swallow the grid. A generated interior sizes it for your page count automatically.
The full set of numbers, including when you need bleed, is in KDP word search interior specs.