KDP Margin Calculator
This interactive tool will calculate the exact margins required for your KDP paperback to pass automated review.
How KDP Margins Work
Amazon KDP requires specific margins to ensure your text isn’t cut off during the printing and trimming process. The most critical margin is the gutter (the inside margin where the pages are bound to the spine).
The thicker your book (the higher the page count), the larger the gutter must be, otherwise the text will disappear into the crease of the book.
Amazon’s gutter margin table
These are KDP’s minimum inside (gutter) margins for paperbacks, from Amazon’s “Set Trim Size, Bleed, and Margins” help page.
| Page count | Minimum gutter (inches) | Minimum gutter (mm) |
|---|---|---|
| 24 to 150 pages | 0.375" | 9.6 mm |
| 151 to 300 pages | 0.5" | 12.7 mm |
| 301 to 500 pages | 0.625" | 15.9 mm |
| 501 to 700 pages | 0.75" | 19.1 mm |
| 701 to 828 pages | 0.875" | 22.3 mm |
Outside, top and bottom margins must be at least 0.25" (6.4 mm) without bleed and at least 0.375" (9.6 mm) with bleed.
Margins we recommend
Amazon’s figures are minimums. Set a book exactly on them and any small shift in printing can push text into the fold, so give yourself room:
| Trim size | Outside | Top and bottom | Gutter |
|---|---|---|---|
| 5" x 8" | 0.5" (12.7 mm) | 0.5" (12.7 mm) | KDP minimum + 0.125" |
| 5.5" x 8.5" | 0.5" (12.7 mm) | 0.625" (15.9 mm) | KDP minimum + 0.125" |
| 6" x 9" | 0.625" (15.9 mm) | 0.75" (19.1 mm) | KDP minimum + 0.125" |
| 7" x 10" | 0.75" (19.1 mm) | 0.75" (19.1 mm) | KDP minimum + 0.125" |
Want us to calculate it for you?
Our AI engine calculates margins automatically based on your exact word count.
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