Every trim size Amazon KDP supports — with genre recommendations, print cost ranking, and industry standards. Filter by your book type to find the right size instantly.
The industry standard for fiction novels. Lowest printing cost per page, fits standard bookshelves, and is what readers expect.
| Trim Size | Inches | CM | Best For | Print Cost |
|---|---|---|---|---|
| 6″ × 9″Most Popular | 6 × 9 | 15.24 × 22.86 | Novels, Non-fiction | ⭐ Lowest |
| 5.5″ × 8.5″Popular | 5.5 × 8.5 | 13.97 × 21.59 | Trade paperback | ⭐ Low |
| 5″ × 8″ | 5 × 8 | 12.7 × 20.32 | Compact novels | ⭐ Low |
| 7″ × 10″Non-fiction | 7 × 10 | 17.78 × 25.4 | Non-fiction, guides | ⭐⭐ Moderate |
| 8.5″ × 11″ | 8.5 × 11 | 21.59 × 27.94 | Workbooks, textbooks | ⭐⭐⭐ Higher |
| 8″ × 10″Children’s | 8 × 10 | 20.32 × 25.4 | Children’s, cookbooks | ⭐⭐ Moderate |
| 8.5″ × 8.5″ | 8.5 × 8.5 | 21.59 × 21.59 | Square picture books | ⭐⭐ Moderate |
| 5.06″ × 7.81″ | 5.06 × 7.81 | 12.85 × 19.84 | Mass market paperback | ⭐ Low |
| 4.25″ × 6.87″ | 4.25 × 6.87 | 10.8 × 17.46 | Pocket books | ⭐ Low |
| 6.14″ × 9.21″ | 6.14 × 9.21 | 15.6 × 23.4 | Trade non-fiction | ⭐ Low |
The trim size is the final physical size of your printed book after it has been cut by Amazon’s printing machines. Choosing the right trim size is one of the most important decisions you’ll make when formatting your KDP book — and it’s one you can’t easily undo after publishing. Amazon does not allow you to change your trim size on an existing listing without unpublishing the book and starting fresh.
The most common mistake new authors make is choosing a trim size based on personal preference rather than genre standards. Readers have expectations about book sizes. A romance novel that comes in an 8.5×11 format looks strange and feels wrong in the hand. A travel photography book in a 5×8 pocket format is too small for the images to be appreciated. Matching your trim size to your genre’s conventions is part of presenting a professional product.
The 6×9 trim size dominates KDP for good reason. It has the lowest printing cost per page of all the standard trim sizes, which means higher royalties at any given price point. It fits standard bookshelf dimensions without awkwardness. It’s large enough for comfortable reading but compact enough to hold comfortably for extended sessions. For the vast majority of novels, memoirs, self-help books, and general non-fiction, 6×9 is the correct choice unless you have a specific reason to use another size.
Large trim sizes like 7×10 and 8.5×11 cost more to print per page and therefore require higher list prices to generate the same royalty. Before choosing a large format, ask yourself honestly whether your content requires it. A non-fiction book with a few charts and tables does not need 7×10 — 6×9 with well-designed two-column layouts can accommodate the same content. Choose large format only when the content genuinely benefits from the extra space.
| Genre | Standard Size | Alternative | Avoid |
|---|---|---|---|
| Fiction Novel | 6″ × 9″ | 5.5″ × 8.5″ | 8.5″ × 11″ |
| Non-Fiction | 6″ × 9″ | 7″ × 10″ | 4.25″ × 6.87″ |
| Children’s Book | 8″ × 10″ | 8.5″ × 8.5″ | 5″ × 8″ |
| Academic/Textbook | 8.5″ × 11″ | 7″ × 10″ | 5″ × 8″ |
| Poetry | 5.5″ × 8.5″ | 6″ × 9″ | 8.5″ × 11″ |
| Workbook/Journal | 8.5″ × 11″ | 8″ × 10″ | 5.5″ × 8.5″ |
FAQ
Common questions about choosing the right trim size for your Amazon KDP paperback.
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