6 by 9 inches, or 152.4 by 228.6 mm, is the standard US trade paperback size. It is Amazon KDP's default, it is available on every major print on demand platform in every paper and binding, and it is the size most self published novels use.
Amazon states the case for it directly: "The most common trim size for books in the U.S. is 6" x 9" (152.4 x 228.6 mm) and is a regular trim size. When setting up your book, this is the default in the "Print Options" section of the Content tab."
The Specification
| Inches | 6 x 9 |
| Millimetres | 152.4 x 228.6 |
| KDP trim class | Regular |
| IngramSpark name | 229 x 152 |
| Lulu name | US Trade |
The KDP trim class matters commercially. A large trim size at KDP is "either more than 6.12 inches (155.5 mm) in width or more than 9 inches (228.6 mm) in height", and large sizes cost more to print. At exactly 6 by 9, you sit just inside the regular band on both dimensions, which is not a coincidence.
Availability
This is the size with no gaps anywhere:
- KDP paperback: yes, in all paper types, and the default.
- KDP hardcover: yes.
- IngramSpark paperback: yes.
- IngramSpark hardcover: all three, case laminate, Digital Cloth and jacketed.
- IngramSpark premium colour: yes.
- KDP Expanded Distribution: yes, on all paper types.
That last row is the one that separates 6 by 9 from the smaller sizes. Expanded Distribution is how a KDP paperback reaches bookshops and libraries, and at 5 by 8 or 5.25 by 8 it is unavailable on premium colour paper. At 6 by 9 every paper qualifies.
Worth knowing separately: KDP hardcovers are excluded from Expanded Distribution entirely, at any size. Amazon states it plainly, that "Hardcover books are not eligible for Expanded Distribution." If bookshop distribution matters, the hardcover has to come from IngramSpark.
Page Counts
At KDP, a 6 by 9 paperback runs 24 to 828 pages on black ink and white paper, 24 to 776 on cream, and 72 to 600 on standard colour. Hardcover is 75 to 550 across every paper.
At IngramSpark the limits come from the paper rather than the size: 18 to 1200 pages on 50lb white, 18 to 1050 on crème, and 18 to 900 on the heavier stocks. The comparison and its consequences are in IngramSpark vs KDP formatting requirements.
When 6 by 9 Is Right, and When It Is Not
Right for: most genre fiction, non-fiction, anything long enough that a smaller page would inflate the page count, and any book where you want the widest possible distribution and binding options with no exceptions to check.
Wrong for: a short novel. This is the real trap. A larger page holds more words, so a 60,000 word novel at 6 by 9 produces a thin book that looks slight on a shelf and feels flimsy in the hand. The same manuscript at 5 by 8 makes a noticeably chunkier, more substantial object. Since spine width is page count multiplied by paper thickness, fewer pages also means a spine too narrow to carry readable text.
Also wrong for literary fiction aiming at a particular shelf presence, where 5 by 8 or 5.5 by 8.5 reads as more considered, and for poetry, where the line length a 6 inch page invites is usually too long.
What Deckle Does
6 by 9 is Deckle's default trim size, matching KDP's default. It is one of six sizes: 5 by 8, 5.5 by 8.5, 6 by 9, 6.14 by 9.21, BoD 135 by 215 mm, and A5 148 by 210 mm.
Two things follow automatically once the size is set. Deckle enforces KDP's page count banded gutter, taking the larger of your inside margin and the platform minimum for the estimated page count. And the print PDF is exported with bleed on three edges, so a 6 by 9 book comes out at 6.125 by 9.25, which is exactly what both KDP and IngramSpark specify.
The default margins for this size are 0.875 inch top, 1.25 inch bottom, 1.25 inch inside and 0.75 inch outside, all comfortably above both platforms' minimums. Adjusting them is covered in book margins and gutter explained.
For the alternatives, see 5x8 book size, 5.5x8.5 book size, and the overview in book trim sizes explained.
Common Mistakes
- Choosing it because it is the default, for a short novel. It will produce a thin book.
- Assuming a KDP hardcover reaches bookshops. Hardcovers are excluded from Expanded Distribution at every size.
- Changing to it late. Trim size determines the text block, so it reflows the entire book.
- Forgetting it is the boundary of the regular trim class. Anything wider or taller costs more to print.
- Using a 6 inch measure for poetry. The line length is usually wrong for verse.
FAQ
Q: Is 6 by 9 the most common novel size? A: Amazon says it is the most common size for US books generally and makes it the default. No source states it for novels specifically.
Q: Does it cost more than a smaller size? A: It is in the same regular trim class as 5 by 8 and 5.5 by 8.5, but a larger page needs fewer of them, so printing cost depends on the resulting page count.
Q: Can I get a 6 by 9 hardcover? A: Yes, at both KDP and IngramSpark, and IngramSpark offers all three hardcover types.
Q: What is 6.14 by 9.21? A: The metric equivalent, 234 by 156 mm, known traditionally as Royal octavo. Deckle offers it as a separate size.
Q: How many words fit on a 6 by 9 page? A: Roughly 300 to 400 in a typical novel setting, though it depends entirely on type size, leading and margins.