KDP Book Sizes: Every Trim Size and How to Choose
Trim size is the width × height of your finished book after printing and cutting. It determines your page count (smaller trim = more pages for the same manuscript), your printing cost (page count drives cost), and whether your book looks "right" on a shelf next to others in its genre. KDP offers 16 standard paperback sizes, 5 hardcover sizes, and custom paperback sizes from 4 × 6 to 8.5 × 11.69 inches.
All KDP paperback trim sizes
| Trim (inches) | Trim (mm) | Typical use |
|---|---|---|
| 5 × 8 | 127 × 203 | Short novels, novellas, poetry |
| 5.06 × 7.81 | 129 × 198 | UK B-format fiction |
| 5.25 × 8 | 133 × 203 | Fiction, memoir |
| 5.5 × 8.5 | 140 × 216 | Fiction, self-help, memoir — safe default |
| 6 × 9 | 152 × 229 | The most common size — fiction & nonfiction |
| 6.14 × 9.21 | 156 × 234 | UK Royal format, trade nonfiction |
| 6.69 × 9.61 | 170 × 244 | Textbooks, technical books |
| 7 × 10 | 178 × 254 | Workbooks, manuals, cookbooks |
| 7.44 × 9.69 | 189 × 246 | Comics-style, educational |
| 7.5 × 9.25 | 190 × 235 | Graphic-heavy nonfiction |
| 8 × 10 | 203 × 254 | Children's books, photo-heavy books |
| 8.25 × 6 | 210 × 152 | Landscape children's books |
| 8.25 × 8.25 | 210 × 210 | Square picture books |
| 8.5 × 8.5 | 216 × 216 | Square children's & coloring books |
| 8.5 × 11 | 216 × 279 | Workbooks, coloring, planners, letter format |
| 8.27 × 11.69 | 210 × 297 | A4 — international workbooks |
Custom paperback trims are allowed from 4 × 6 in up to 8.5 × 11.69 in — but custom sizes lose Expanded Distribution eligibility, so stick to standard sizes unless you have a specific reason.
Hardcover trim sizes
Hardcover (case laminate) is available in five sizes only: 5.5 × 8.5, 6 × 9, 6.14 × 9.21, 7 × 10, and 8.25 × 11 inches, all from 75 to 550 pages. Remember: the hardcover case is physically larger than the trim size — see the spine chart for how the wrap and hinge change your cover file.
Page count limits by paper type
| Interior | Paperback range | Hardcover range |
|---|---|---|
| Black & white · White | 24 – 828 | 75 – 550 |
| Black & white · Cream | 24 – 776 | 75 – 550 |
| Black & white · Groundwood | 24 – 812 | — |
| Premium color · White | 24 – 828 | 75 – 550 |
| Standard color · White | 72 – 600 | — |
How to choose (60-second version)
- Novel or narrative nonfiction → 6 × 9 if your manuscript is long (keeps page count and print cost down), 5.5 × 8.5 or 5.25 × 8 if it's short (fills more pages, looks more substantial).
- Children's picture book → 8.5 × 8.5 square or 8.25 × 6 landscape. Go premium color; standard color's 72-page minimum usually rules it out.
- Workbook / planner / coloring book → 8.5 × 11. Buyers expect writing room.
- Poetry → 5 × 8 or 5.25 × 8.
- Cookbook / manual → 7 × 10 or 7.5 × 9.25.
One warning from the print-cost side: page count, not trim size, drives KDP's printing cost for black & white books — a 6 × 9 book fits more words per page than 5 × 8, so the bigger trim is usually the cheaper choice for long manuscripts.