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Book Spine Width Calculator
Enter your page count and paper type. See spine width, cover dimensions, and whether your spine can hold text.
Your Book
Spine Width
0.750 inches · 19.05 mm
0.750"
0" 3"
Formula: 300 × 0.0025 + 0.00 = 0.750"
Full Cover Dimensions
Back Cover 5.5"
Spine 0.750"
Front Cover 5.5"
Full cover width (no bleed) 11.750"
Full cover width (with bleed) 12.000"
Full cover height (no bleed) 8.5"
Full cover height (with bleed) 8.75"
Pixels at 300 DPI (width) 3600 px
Pixels at 300 DPI (height) 2625 px
Quick Reference Table
Spine widths for common page counts using Cream (B&W) paper.
| Pages | Spine Width | Can Print Spine Text? |
|---|
Done calculating? Now you need to format the interior to match.
Cambric calculates spine width, cover dimensions, and margins from your actual manuscript automatically. No spreadsheets, no guessing.
Frequently Asked Questions
How do I calculate my book's spine width?
Spine width = page count × paper thickness factor. For KDP cream paper: pages × 0.0025". For white paper: pages × 0.002252". Add 0.06" for hardcover case wrap. For example, a 300-page cream paperback has a spine of 300 × 0.0025 = 0.750".
What paper thickness should I use for KDP?
KDP offers cream (0.0025"/page) and white (0.002252"/page) for black-and-white interiors, plus premium color (0.002347"/page) and standard color (0.002252"/page). Cream is the most popular choice for fiction — it's easier on the eyes for long reading sessions and gives a thicker, more substantial feel to the book.
Does IngramSpark use the same spine calculation?
IngramSpark uses similar but not identical values. Their 50# cream is approximately 0.0025"/page and 50# white is approximately 0.002252"/page. The values in this calculator are a close match, but always verify with IngramSpark's official cover template generator before submitting your final cover file.
What is the minimum spine width for text on the spine?
KDP requires at least 0.5" spine width to print text (title and author name) on the spine. Below that, your cover should have a blank spine. Most books over 100 pages on cream paper meet this threshold. A 200-page cream paperback has a 0.500" spine — right at the minimum.
How do I use the spine width for my cover?
Full cover width = back cover width + spine width + front cover width + bleed (0.125" on each side). So for a 5.5" × 8.5" book: 5.5 + spine + 5.5 + 0.25 = 11.25 + spine. Your cover designer needs this total width plus the total height (trim height + 0.25" for bleed) to create a print-ready cover file at 300 DPI.
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Next Step Know your spine width?
Know your spine width?
Build the book.
Cambric calculates spine width from your actual manuscript and generates cover templates with exact dimensions for your designer.