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Free Book Spine Calculator

Calculate your book's spine width instantly for Amazon KDP, IngramSpark, and other print-on-demand services. Get exact measurements in inches and millimeters.

Spine Calculator

Total interior pages (must be even for print books)

Spine Width

0.45"
Inches
11.44mm
Millimeters

Spine text allowed! Your book has enough pages to include text on the spine.

Spine Width Reference

KDP Requirements

  • Minimum: 24 pages
  • Maximum: 828 pages (paperback)
  • Spine text: 79+ pages (white)
  • Spine text: 56+ pages (cream)

IngramSpark

  • Minimum: 18 pages
  • Maximum: 800 pages
  • More paper options
  • Global distribution

Cover Design Tips

  • Always add 0.125" bleed
  • Keep text 0.25" from edges
  • Center spine text carefully
  • Use high-res images (300dpi)
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