# KDP spine width calculator

Source: https://kdpbook.io/kdp/spine-width-calculator · Updated 2026-10-15

Calculate your KDP paperback or hardcover spine width from page count and paper type, and check whether the spine can carry text, with KDP’s per-page factors.

Checked against KDP Help on 2026-09-26.

## KDP spine width by page count (paperback)

Spine width = printed page count × the paper's thickness per page (KDP prints an even number of pages). "not offered": above KDP's page limit for that paper on a 6 × 9 in book. KDP prints spine text only on books with more than 79 pages.

| Pages | Printed pages | B&W white | B&W cream | Premium color | Spine text allowed |
| --- | --- | --- | --- | --- | --- |
| 24 | 24 | 0.054 in | 0.06 in | 0.056 in | No |
| 50 | 50 | 0.113 in | 0.125 in | 0.117 in | No |
| 75 | 76 | 0.171 in | 0.19 in | 0.178 in | No |
| 100 | 100 | 0.225 in | 0.25 in | 0.235 in | Yes |
| 150 | 150 | 0.338 in | 0.375 in | 0.352 in | Yes |
| 200 | 200 | 0.45 in | 0.5 in | 0.469 in | Yes |
| 250 | 250 | 0.563 in | 0.625 in | 0.587 in | Yes |
| 300 | 300 | 0.676 in | 0.75 in | 0.704 in | Yes |
| 400 | 400 | 0.901 in | 1 in | 0.939 in | Yes |
| 500 | 500 | 1.126 in | 1.25 in | 1.173 in | Yes |
| 600 | 600 | 1.351 in | 1.5 in | 1.408 in | Yes |
| 700 | 700 | 1.576 in | 1.75 in | 1.643 in | Yes |
| 800 | 800 | 1.802 in | not offered | 1.878 in | Yes |

Any page count: https://kdpbook.io/kdp/spine-width-calculator