Trim size and ink/paper are the first two choices you make for a KDP print book, and the only ones you can’t change after publishing. They decide your page limits, spine width, printing cost and royalties.
Trim sizes
The trim size is the size of the finished book. KDP offers 16 standard paperback sizes and 5 hardcover sizes (5.5 × 8.5, 6 × 9, 6.14 × 9.21, 7 × 10, 8.25 × 11 in). Paperbacks can also use a custom size between 4 × 6 in and 8.5 × 11.69 in.
See every size drawn to scale, with its page limits, in the trim size tool.
Regular vs large trims
KDP calls a trim large when it is wider than 6.12 in or taller than 9 in. Large trims cost more to print per page. 6 × 9 in is the biggest size that still counts as regular, one reason it is so popular. Large sizes: 6.14 × 9.21, 6.69 × 9.61, 7 × 10, 7.44 × 9.69, 7.5 × 9.25, 8 × 10, 8.25 × 6, 8.25 × 8.25, 8.5 × 8.5, 8.5 × 11, 8.27 × 11.69, 8.25 × 11 in.
The five ink and paper options
| Option | Best for | Pages (most trims) |
|---|---|---|
| Premium color · white paper 60–71 lb (88–105 GSM) · paperback & hardcover | Rich, vivid color. Best for full-page illustrations. | 24–828 |
| Standard color · white paper 50–61 lb (74–90 GSM) · paperback only | Cheaper color for text-heavy books. | 72–600 |
| Black & white · white paper 50–61 lb (74–90 GSM) · paperback & hardcover | Non-fiction, workbooks, coloring books. | 24–828 |
| Black & white · cream paper 50–61 lb (74–90 GSM) · paperback & hardcover | The classic look for novels. Slightly thicker spine. | 24–776 |
| Black & white · groundwood paper 45 lb (60 GSM) · paperback only | Lighter paper, about 5% lower print cost per page. | 24–812 |
Page limits are lower on the 8.25 in and 8.5 in wide trims, and standard color isn’t available on A4 or on Amazon.com.au. Groundwood is the newest option: a lighter, cheaper paper that isn’t suited to heavy ink coverage.
What each option costs
Printing cost and spine width for the same 6 × 9 in, 200-page paperback on Amazon.com:
| Option | Spine | Printing cost |
|---|---|---|
| Premium color · white paper | 0.469 in | $14.00 |
| Standard color · white paper | 0.45 in | $6.10 |
| Black & white · white paper | 0.45 in | $3.40 |
| Black & white · cream paper | 0.5 in | $3.40 |
| Black & white · groundwood paper | 0.47 in | $3.28 |
Compare any configuration across marketplaces with the printing cost calculator.
Choosing for your book
- Novel: 5 × 8, 5.5 × 8.5 or 6 × 9 in, black and white on cream.
- Non-fiction: 6 × 9 in (or 7 × 10 in with many figures), black and white on white.
- Picture book: 8.5 × 8.5 in or 8 × 10 in, premium color with bleed.
- Illustrated book over 72 pages: consider standard color to keep the price reasonable.
- Coloring, activity and workbooks: 8.5 × 11 in, black and white on white.
Every kdpbook book type starts from a trim and paper that suit it, and only offers combinations KDP accepts for your page count.