How to calculate spine width ​

The spine calculations are for most people a confusing element. For the most cases, our client will implement the calculations directly into their system. For that, we provide the formulas for the calculations.


Formula for spine width calculation ​

mm Spine in mm = (paperweight in gsm x paper bulk x (page count / 2)) / 1000 + (2 x cover thickness)


inch Spine in inch = ((paperweight in gsm x paper bulk x (page count / 2)) / 1000 + (2 x cover thickness)) / 25.4


The paper bulk values used by Cloudprinter is: ​

Paper typeBulk value
MCG0.80
MCS0.90
ECB1.20
OFF1.22

The cover thickness values used by Cloudprinter is: ​

Cover typeThickness in mm
Case Wrap / Hardcover - 3 mm material (default)3.0
Case Wrap / Hardcover - 2 mm material2.0
Perfect Binding / Softcover0.5

Spine width calculator ​

We have made a guideline tool for you to easily calculate the spine based on the paperweight, paper type, and cover type.

You find the calculator here: Spine width calculator


Disclaimer ​

This spine width calculation uses average bulk values. The characteristics of the paper used by different print partners may vary.

Case Wrap books mostly use pre-cut cardboard in the spine. The cardboard is therefore in a number of fixed sizes. These sizes may vary between print partners.