Book spine width calculator
Your spine grows with every page you add. Enter your page count and paper to see how wide your spine will be, and how big to make your cover file.
- Spine width
- 0.52 in
- In millimeters
- 13.2 mm
- Pages alone (book block)
- 0.5 in
- Full cover file, with bleed
- 12.77 x 9.25 in
Estimates. The cover stock adds a little to the pages. Paper thickness varies from mill to mill, so always build your final cover from your printer's template.
Get the free cover templateHow spine width is calculated
Spine width is your page count divided by your paper's pages per inch (PPI), plus a little for the cover. A 200 page book on paper that runs 400 pages per inch has a book block half an inch thick. A softcover adds the thickness of its cover stock, and a hardcover adds the boards that make up the case.
Count every page
Page count means every page in your interior file: the title page, the copyright page, blank pages and everything at the back. One sheet printed on both sides is two pages.
Why your printer's template matters
PPI changes from paper to paper, even at the same weight, so a spine worked out with one printer's numbers may not match another's. Finish your inside pages first, then build your final cover from the template for your exact book. In our spec picker, the spine width updates as you go, and the free cover template is already the right size.