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KDP Spine & Cover Calculator

Calculate the exact spine caliper for 50# Cream, 50# White, and Groundwood paperbacks on Amazon KDP. Generates instant, zero-error TikZ and LaTeX \geometry blocks.

Official KDP Preflight Math

Interactive KDP Spine & Gutter Calculator

Page Count 264 pages

24 pp (Min) 264 pp (Typical) 800 pp (Max)

Paper Type

Cream 50# 0.0025"/p

White 50# 0.00225"/p

Groundwood 0.00235"/p

Trim Size (Width × Height)

Spine Thickness 16.76 mm 0.660 in

Required Gutter 22.0 mm 0.866 in (Safe)

Total Cover Size 280.2 × 204.8 mm 11.03" × 8.06"

Generated \geometry & TikZ Dimensions

% Cover Dimensions for 264 pp Cream Paper
\usepackage[
  paperwidth=280.2mm,
  paperheight=204.8mm,
  margin=0mm
]{geometry}

1. Cream Paper Thickness

Cream paper uses a multiplier of 0.0025 inches/page (0.0635 mm/page). For a 264-page book, spine width is exactly 16.76 mm (0.660 in).

2. Gutter Margins

For books between 151 and 300 pages, KDP mandates a minimum inside gutter margin of 0.5 inches (12.7 mm). We recommend 22–23 mm for optimal spine reading ergonomics.

3. 0.125" Bleed Rules

All paperback covers require 0.125" (3.175 mm) bleed on all four sides. The total canvas width is: Bleed + Back + Spine + Front + Bleed.