80-page threshold
KDP cover guidance says spine text is printed only on books with more than 79 pages, while Cover Creator uses an 80-page minimum. Below that threshold, keep the spine blank and let the cover wrap through the center.
Even above 80 pages, avoid oversized spine text and keep it away from the fold edges.
Design implication
A narrow spine gives little room for titles, author names, or imprint marks. Recalculate after paper type or page count changes.
Example trim and paper references
| Preset | Use case |
|---|---|
| 5 x 8 in | Compact fiction and nonfiction paperbacks. |
| 5.5 x 8.5 in | Common memoir, fiction, and trade paperback size. |
| 6 x 9 in | Popular trade paperback and low-content book size. |
| 7 x 10 in | Workbooks, manuals, and larger nonfiction. |
FAQ
Does 79 pages allow spine text?
Plan as no. This calculator warns below 80 pages and recommends verifying in KDP Previewer.
Does paper type affect spine text?
Paper type affects spine width when the verified paper factor differs, so it affects how much space is available for text after the page threshold is met.