Free calculator
Book Margin & Gutter Calculator
Find the minimum inside (gutter) and outside margins for your page count, plus comfortable recommended margins and the resulting text block.
—Min. inside margin (KDP)
—Min. outside margin
—Recommended margins
—Text block
—PDF page size
How it works
The thicker the book, the more of the inside margin disappears into the binding. KDP's minimum inside margins are 0.375 in (24–150 pages), 0.5 in (151–300), 0.625 in (301–500), 0.75 in (501–700) and 0.875 in (701–828). Outside margins must be at least 0.25 in, or 0.375 in with bleed.
Frequently asked questions
Should the inside margin be bigger than the outside?
Yes, for perfect-bound books: the gutter loses space to the curve of the binding.