How do I calculate my book's spine width?

Getting your spine width right before you build your cover file saves time and avoids costly revisions. Spine width is determined by three variables: page count, paper stock, and binding type and even small differences in paper thickness can shift the measurement enough to affect your cover layout.

Bradford & Bigelow's spine size calculator does the math for you, so you can get an accurate measurement before you open your design file.

What you'll need before you calculate

To get an accurate spine width, have the following ready:

• Final or estimated page count
• Paper stock PPI (pages per inch)
• Binding type (perfect bound or case bound)

If your page count isn't finalized yet, run the calculator with your estimated count, you can always recalculate once pages are locked.

Calculate your spine width

Using your spine width in your cover file

Once you have your measurement, add it to your cover template as the spine panel width. Your front cover, spine, and back cover should be built as a single flat file with bleed on all outer edges.

A note on rounding and tolerance

Spine width calculations are based on manufacturer PPI (pages per inch) values for each paper stock. Finished spine width can vary slightly due to binding pressure and paper lot variation. We recommend building your spine with this in mind and avoid placing critical text or design elements too close to the spine edges.

Need help with your cover file?

If you have questions about your cover setup or want us to review your file before submission, please contact us.