KDP calls 6 × 9 inches the most common trim size for books in the US. These are the numbers a 6 × 9 paperback needs, in one place.
Page size
| Without bleed | 6 × 9″ (152.4 × 228.6 mm) |
| With bleed | 6.125 × 9.25″ (155.6 × 235 mm) |
Bleed is for pages with something that runs to the edge. KDP bleed or no bleed explains when a book needs it.
Margins
| Page count | Inside margin, at least |
|---|---|
| 24 to 150 | 0.375″ (9.6 mm) |
| 151 to 300 | 0.5″ (12.7 mm) |
| 301 to 500 | 0.625″ (15.9 mm) |
| 501 to 700 | 0.75″ (19.1 mm) |
| 701 to 828 | 0.875″ (22.3 mm) |
The outside, top and bottom margins must be at least 0.25″, or 0.375″ with bleed. These are minimums, and How KDP gutter margins work explains why the inside one depends on the final page count.
Page count
KDP prints a 6 × 9 paperback in black ink from 24 to 828 pages on white paper, 24 to 776 on cream and 24 to 812 on groundwood.
Spine and cover
| Pages | White paper | Cream paper |
|---|---|---|
| 200 | Spine 0.450″, cover 12.700 × 9.25″ | Spine 0.500″, cover 12.750 × 9.25″ |
| 300 | Spine 0.676″, cover 12.926 × 9.25″ | Spine 0.750″, cover 13.000 × 9.25″ |
| 400 | Spine 0.901″, cover 13.151 × 9.25″ | Spine 1.000″, cover 13.250 × 9.25″ |
The cover sizes include 0.125″ of bleed on every outside edge. The free spine calculator gives the size for any page count, and A KDP paperback cover in Canva shows how the sum is made.
KDP allows spine text from 79 pages. Torcul puts it on from 112 pages on white paper and 101 on cream, where a 7-point line fits; KDP minimum page count explains the difference.
Pages for a word count
| Words | Pages at 6 × 9 |
|---|---|
| 40,000 | 144 |
| 60,000 | 214 |
| 80,000 | 282 |
| 100,000 | 350 |
Measured on a typeset novel in English. How many pages will my book be? gives the other trim sizes and how the test book was set.
What Torcul does
6 × 9 is Torcul's default trim size. It fits the inside margin to the final page count and makes the cover for that count and paper.
Sources
None of this guarantees that KDP will accept a file. KDP changes its help pages, so check the date on this one.