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KDP margins and gutter by page count

The minimum outside margins and the inside gutter, which grows with the page count.

Checked November 9, 2026Plain text version

Margins keep your text from being cut off or lost in the spine. KDP sets minimums; most books look better with a little more.

Outside margins

  • Without bleed: at least 0.25 in (6.3 mm).
  • With bleed: at least 0.375 in (9.5 mm).

Inside margin (gutter)

The thicker the book, the more of the page curves into the spine, so the inside margin grows with the page count:

PagesMinimum gutter
24–1500.375 in (9.5 mm)
151–3000.5 in (12.7 mm)
301–5000.625 in (15.9 mm)
501–7000.75 in (19.0 mm)
701–8280.875 in (22.2 mm)

Sources

KDP help pages, checked November 7, 2026. KDP changes its rules without notice; the linked page has the final word.

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