Covers
Book Spine Width Charts by Trim Size & Page Count
Pick a trim size to see spine widths and full-wrap cover dimensions for page counts from 24 to 828.
Spine width (white paper) at a glance
| Trim | 100 pp | 200 pp | 300 pp | 400 pp | 500 pp |
|---|---|---|---|---|---|
| 5 x 8 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 5.06 x 7.81 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 5.25 x 8 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 5.5 x 8.5 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 6 x 9 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 6.14 x 9.21 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 6.69 x 9.61 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 7 x 10 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 7.5 x 9.25 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 8 x 10 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 8.5 x 8.5 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
| 8.5 x 11 in | 0.225 in | 0.45 in | 0.676 in | 0.901 in | 1.126 in |
Choose a trim size
5 x 8 in
5 x 8 in
5.06 x 7.81 in
5.06 x 7.81 in
5.25 x 8 in
5.25 x 8 in
5.5 x 8.5 in
5.5 x 8.5 in Digest
6 x 9 in
6 x 9 in US Trade
6.14 x 9.21 in
Royal (6.14 x 9.21 in)
6.69 x 9.61 in
6.69 x 9.61 in
7 x 10 in
7 x 10 in Executive
7.5 x 9.25 in
7.5 x 9.25 in
8 x 10 in
8 x 10 in
8.5 x 8.5 in
8.5 x 8.5 in Square
8.5 x 11 in
8.5 x 11 in Letter
How spine width is calculated
For print-on-demand paperbacks, spine width is the page count multiplied by the thickness of one page of the chosen paper:
spine = pages × paper factor
KDP publishes 0.002252 in per page for white paper, 0.0025 in for cream, 0.002252 in for standard colour and 0.002347 in for premium colour. Offset printers specify paper by PPI (pages per inch), in which case spine = pages ÷ PPI.
The full cover is bleed + back cover + spine + front cover + bleed wide and trim height + 2 × bleed tall.
Thickness by page count (any trim)
- 24 pages
- 32 pages
- 40 pages
- 48 pages
- 56 pages
- 64 pages
- 72 pages
- 80 pages
- 90 pages
- 100 pages
- 110 pages
- 120 pages
- 130 pages
- 140 pages
- 150 pages
- 160 pages
- 170 pages
- 180 pages
- 190 pages
- 200 pages
- 210 pages
- 220 pages
- 230 pages
- 240 pages
- 250 pages
- 260 pages
- 270 pages
- 280 pages
- 290 pages
- 300 pages
- 310 pages
- 320 pages
- 330 pages
- 340 pages
- 350 pages
- 360 pages
- 370 pages
- 380 pages
- 390 pages
- 400 pages
- 410 pages
- 420 pages
- 430 pages
- 440 pages
- 450 pages
- 460 pages
- 470 pages
- 480 pages
- 490 pages
- 500 pages
- 520 pages
- 540 pages
- 560 pages
- 580 pages
- 600 pages
- 620 pages
- 640 pages
- 660 pages
- 680 pages
- 700 pages
- 720 pages
- 740 pages
- 760 pages
- 780 pages
- 800 pages
- 828 pages