Spine Width and Cover Size for a 6 x 9 in KDP Paperback
Find the spine width and full wrap cover size for a 6 x 9 in paperback on Amazon KDP. The tables use the paper thickness KDP publishes for each paper type, and the calculator below works out any page count you choose.
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At a glance
| Trim size | 6 x 9 in (152.4 x 228.6 mm) |
|---|---|
| Full cover height | 9.25 in (trim height plus 0.125 in bleed top and bottom) |
| Bleed | 0.125 in on all outer edges |
| Spine at 300 pages | 0.6756 in on white paper, 0.75 in on cream paper |
| Page count KDP allows | 24 to 828 pages on black ink and white paper |
| Printing cost class | Regular trim |
Calculate your own page count
Cover size
Spine width by page count for a 6 x 9 in book
Spine width is the page count multiplied by the paper thickness KDP publishes: 0.002252 in per page for black ink on white paper, 0.0025 in for cream paper, 0.002252 in for standard color and 0.002347 in for premium color. The trim size does not change it, so these spine widths apply to any KDP paperback with the same page count and paper.
Spine width of a 6 x 9 in KDP paperback
| Pages | Black ink, white paper | Black ink, cream paper | Standard color ink | Premium color ink |
|---|---|---|---|---|
| 100 | 0.2252 in (5.72 mm) | 0.25 in (6.35 mm) | 0.2252 in (5.72 mm) | 0.2347 in (5.96 mm) |
| 150 | 0.3378 in (8.58 mm) | 0.375 in (9.52 mm) | 0.3378 in (8.58 mm) | 0.3521 in (8.94 mm) |
| 200 | 0.4504 in (11.44 mm) | 0.5 in (12.7 mm) | 0.4504 in (11.44 mm) | 0.4694 in (11.92 mm) |
| 250 | 0.563 in (14.3 mm) | 0.625 in (15.88 mm) | 0.563 in (14.3 mm) | 0.5868 in (14.9 mm) |
| 300 | 0.6756 in (17.16 mm) | 0.75 in (19.05 mm) | 0.6756 in (17.16 mm) | 0.7041 in (17.88 mm) |
| 350 | 0.7882 in (20.02 mm) | 0.875 in (22.23 mm) | 0.7882 in (20.02 mm) | 0.8215 in (20.86 mm) |
| 400 | 0.9008 in (22.88 mm) | 1 in (25.4 mm) | 0.9008 in (22.88 mm) | 0.9388 in (23.85 mm) |
| 450 | 1.0134 in (25.74 mm) | 1.125 in (28.58 mm) | 1.0134 in (25.74 mm) | 1.0562 in (26.83 mm) |
| 500 | 1.126 in (28.6 mm) | 1.25 in (31.75 mm) | 1.126 in (28.6 mm) | 1.1735 in (29.81 mm) |
Full wrap cover size for a 6 x 9 in book
The full wrap cover is the back cover, the spine and the front cover side by side, plus a 0.125 in bleed on every outer edge. Width is 2 x 6 in plus the spine width plus 2 x 0.125 in. Height is 9 in plus 2 x 0.125 in, which is 9.25 in.
Full wrap cover size (width x height) of a 6 x 9 in KDP paperback
| Pages | Black ink, white paper | Black ink, cream paper | Standard color ink | Premium color ink |
|---|---|---|---|---|
| 100 | 12.4752 x 9.25 in | 12.5 x 9.25 in | 12.4752 x 9.25 in | 12.4847 x 9.25 in |
| 150 | 12.5878 x 9.25 in | 12.625 x 9.25 in | 12.5878 x 9.25 in | 12.6021 x 9.25 in |
| 200 | 12.7004 x 9.25 in | 12.75 x 9.25 in | 12.7004 x 9.25 in | 12.7194 x 9.25 in |
| 250 | 12.813 x 9.25 in | 12.875 x 9.25 in | 12.813 x 9.25 in | 12.8368 x 9.25 in |
| 300 | 12.9256 x 9.25 in | 13 x 9.25 in | 12.9256 x 9.25 in | 12.9541 x 9.25 in |
| 350 | 13.0382 x 9.25 in | 13.125 x 9.25 in | 13.0382 x 9.25 in | 13.0715 x 9.25 in |
| 400 | 13.1508 x 9.25 in | 13.25 x 9.25 in | 13.1508 x 9.25 in | 13.1888 x 9.25 in |
| 450 | 13.2634 x 9.25 in | 13.375 x 9.25 in | 13.2634 x 9.25 in | 13.3062 x 9.25 in |
| 500 | 13.376 x 9.25 in | 13.5 x 9.25 in | 13.376 x 9.25 in | 13.4235 x 9.25 in |
Worked example: 300 pages on white paper
6 x 9 in, 300 pages, black ink, white paper
| Spine width | 0.6756 in (17.16 mm) |
|---|---|
| Full cover width | 12.9256 in (328.3 mm) |
| Full cover height | 9.25 in (235 mm) |
| Pixels at 300 dpi | 3878 x 2775 px (spine 203 px) |
| Back cover ends at | 6.125 in from the left edge |
| Front cover starts at | 6.8006 in from the left edge |
Before you design the cover
- KDP allows these page counts for a 6 x 9 in book: black ink, white paper: 24 to 828 pages; black ink, cream paper: 24 to 776 pages; black ink, groundwood paper: 24 to 812 pages; standard color ink: 72 to 600 pages; premium color ink: 24 to 828 pages.
- Under 80 pages KDP Cover Creator does not allow spine text, so leave the spine blank.
- KDP does not publish a spine factor for groundwood paper, so use KDP's own cover calculator if you choose it.
- KDP prices printing as regular or large trim (large means wider than 6.12 in or taller than 9 in). A 6 x 9 in book is a regular trim.
- Pixel sizes use 300 dpi. Always load your finished cover into KDP's previewer; it is the final check.
Frequently asked questions
What is the spine width of a 6 x 9 in book with 300 pages?
On black ink and white paper it is 0.6756 in (17.16 mm). On cream paper it is 0.75 in (19.05 mm), on standard color 0.6756 in (17.16 mm) and on premium color 0.7041 in (17.88 mm).
How big is the full cover for a 6 x 9 in paperback with 300 pages?
On white paper the full wrap cover is 12.9256 x 9.25 in (328.3 x 235 mm), or 3878 x 2775 px at 300 dpi. That includes 0.125 in of bleed on every outer edge.
Does the trim size change the spine width?
No. Spine width depends only on the page count and the paper type. The trim size changes the width and height of the cover, not the spine.
Can I put text on the spine of a 6 x 9 in book with 60 pages?
KDP Cover Creator does not allow spine text under 80 pages, so leave the spine blank. At 60 pages on white paper the spine is only 0.1351 in (3.43 mm) wide.
How accurate are these figures?
They follow KDP's paper thickness and bleed rules as published on the platform's own help pages, last checked 2026-10-15. Treat them as planning numbers and confirm the final figure on the platform's own screen before you publish.
Keep going
5.5 x 8.5 in spine width and cover size
Spine and full wrap cover size for 100 to 500 pages on every KDP paper type.
OpenReferenceKDP paperback printing cost table
Printing cost, minimum list price and royalty examples by page count and ink type.
OpenReferenceKDP page counts, margins and bleed
Page count limits by trim size and paper, minimum margins and page sizes with bleed.
OpenGuideHow to Size a Paperback Cover and Calculate the Spine
The spine and cover size formulas, a worked 6 x 9 example and a briefing checklist for designers.
OpenFree toolCover & Spine Calculator
Spine width, full cover size and pixel dimensions for every KDP trim size.
OpenSources and how we checked
Every number on this page is calculated from the platform figures in our rules file, using the same code as the free tool, and last checked 2026-10-15. These are the official pages the figures come from.
These are planning estimates, not financial or legal advice. Confirm the final figure on the platform's own screen before you publish.