Choose the Right Trim Size
Your trim size dictates the physical dimensions of your printed book. Choosing the right size is crucial—it affects your page count, your printing costs, and how your book feels in a reader’s hands.
Standard KDP Trim Sizes
| Trim Size (Inches) | Trim Size (mm) | Best For |
|---|---|---|
| 5" x 8" | 127 x 203 mm | Novellas, short memoirs, literary fiction. |
| 5.5" x 8.5" | 140 x 216 mm | Trade paperbacks, standard fiction, narrative non-fiction. |
| 6" x 9" | 152 x 229 mm | A common standard. Thrillers, sci-fi, fantasy, business books. |
| 7" x 10" | 178 x 254 mm | Workbooks, manuals, academic texts. |
| 8" x 10" | 203 x 254 mm | Children’s books, art books, large manuals. |
| 8.5" x 11" | 216 x 279 mm | Textbooks, sheet music, coloring books. |
How Trim Size Affects Cost
KDP printing cost is a fixed cost plus a per-page cost, and both vary by trim size, ink and paper. A larger trim size can lower your page count, but larger trims can also carry a higher fixed and per-page cost — so a bigger trim does not reliably reduce your printing cost or raise your royalties. Check KDP’s live pricing calculator for your specific trim, ink and page count.
However, if you choose a trim size that is too large for your genre, your book may look amateurish or feel flimsy (like a magazine rather than a novel).
Not sure which to choose?
publishing.co.uk defaults to the industry standard 6x9, but you can select any size at checkout.
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