Spine Width Estimates
How to calculate spine width estimates. Get the final measurement form us!
Spine Width Estimate/Calculation Formula.
Maybe you need an estimate before your book is finalized, so here is the information to calculate sine width. Just remember to get the final measurements from us before sending us the PDFs. The number of pages per inch (ppi in this case) counts determine spine width.
Divide the page count by the number of pages per inch (ppi) noted in the charts below. Add 0.03″ to allow for gathered signatures, cover and glue. Example for 184 page book printed on 140 gsm matte art: 184 pages divided by 348 ppi equals 0.53″ plus 0.03″ equals a spine width of 0.56″.
Hardcover spine width estimate
Add thickness of front and back boards. Gloss is thinner than the same weight of matte.
Matte Art — (Coated)
- 80 gsm = 651 ppi
- 100 gsm = 546 ppi
- 120 gsm = 454 ppi
- 140 gsm = 348 ppi
- 180 gsm = 282 ppi
Gloss Art — (Coated)
- 80 gsm = 726 ppi
- 100 gsm = 605 ppi
- 120 gsm = 535 ppi
- 140 gsm = 405 ppi
- 180 gsm = 332 ppi
Wood Free — (Uncoated)
- 80 gsm = 552 ppi
- 100 gsm = 462 ppi
- 120 gsm = 552 ppi
- 140 gsm = 552 ppi
- 180 gsm = 552 ppi
The truth about spine width estimates.
Spine width estimates are often a waste of time. Yes, I said that and this is why. So often at Star Print Brokers, we get book cover files sent to us and the width is wrong. Usually that is because the author or graphic artist estimates a spine width from when they did a few print on-demand books, or book printing with another company.
You see, the spine varies and we calculate is by paper and cover thickness.
The spine width estimate is important so that the graphic designer knows what size to make the title on the spine.
We will provide a template with the measurements and spine width for dust jacket, cover, and/or cover wrap. Before we can provide you with the measurements, we first need to know exactly how many pages are in the book, and determine the paper thickness and finish.
The spine width estimate formula is approximate. We provide a template when you print books with us. The estimate should be based on the particular printing partner or bindery that we are using.
This spine width estimate chart provides a close enough estimate for preliminary artwork. See this handy fractions, inches, MM conversion chart.
If you have questions you can call us or send a message through our contact page. We will provide the exact spine width for you or your designer, as well as the soft cover cover or hardcover cover wrap dimensions for printing on onset press. Files are ideally set-up in InDesign.
While you have use these spine width calculations for any place that will print or output your book, be sure to ask us or them to provide the final spine width or template measurements.