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KDP Margins and Gutter Requirements
For a paperback without bleed, KDP needs at least 0.25 in on the top, bottom and outside edges and an inside (gutter) margin that grows with page count: 0.375 in for 24–150 pages, up to 0.875 in for 701–828 pages. A 240-page book needs a 0.5 in gutter.
- Gutter (inside)
- 0.500 in12.7 mm
- Top, bottom, outside
- ≥ 0.250 inno bleed · 0.375 in with bleed
- Text area per page
- 5.250 × 8.500 inlargest block that fits inside the minimum margins
KDP gutter by page count
| Page count | Inside (gutter) margin | Outside margins, no bleed | Outside margins, with bleed |
|---|---|---|---|
| 24–150 | 0.375 in (9.6 mm) | ≥ 0.25 in (6.4 mm) | ≥ 0.375 in (9.6 mm) |
| 151–300 | 0.5 in (12.7 mm) | ≥ 0.25 in (6.4 mm) | ≥ 0.375 in (9.6 mm) |
| 301–500 | 0.625 in (15.9 mm) | ≥ 0.25 in (6.4 mm) | ≥ 0.375 in (9.6 mm) |
| 501–700 | 0.75 in (19.1 mm) | ≥ 0.25 in (6.4 mm) | ≥ 0.375 in (9.6 mm) |
| 701–828 | 0.875 in (22.3 mm) | ≥ 0.25 in (6.4 mm) | ≥ 0.375 in (9.6 mm) |
Odd pages (right-hand) have the gutter on the left, even pages on the right. Anything outside the live area — text, page numbers, headers, images that don’t bleed — triggers KDP’s “content outside margins” error.
Already exported your PDF? Check it for free: we measure every page against these margins and can rescale the whole book uniformly to fit, without changing page numbers.
Source: KDP Help: Set Trim Size, Bleed, and Margins. Checked .
How to set KDP margins
- Look up the gutter for your final page count. Round up: a book that might grow past 300 pages should use 0.625 in.
- Turn on mirrored margins. Word: Layout → Margins → Mirrored. The gutter follows the spine.
- Set outside margins to at least 0.25 in. Most designers use 0.5–0.75 in for comfortable reading.
- Export a PDF and check it. Page numbers and headers are the usual offenders.
When to use it
- Setting up a Word, Google Docs or Affinity document for KDP
- Fixing a “content outside margins” rejection
- Your page count changed and crossed a gutter band
When not to
- Hardcovers: KDP’s hardcover margins differ
- Full-bleed picture books: outside margins are 0.375 in and our fix doesn’t support bleed yet
At a glance
- Free: full check report, cover/spine calculator, royalty calculator. No account needed.
- Paid: $9 per book, one-time — fixed interior PDF + full-wrap cover (PDF, PNG, layered PSD). Re-download for 30 days.
- Files are processed in your browser; your manuscript is never uploaded to our servers.
- Pagination never changes; text is scaled uniformly (default keeps ≥ 0.08″ clearance inside KDP's margins).
- Supports paperback, no-bleed interiors, trim sizes 5×8 to 8.5×11, 24–828 pages. Bleed (picture books) and hardcover: coming soon.
- Refund: if KDP rejects a problem we fixed, full refund.
- Not affiliated with Amazon. KDP's previewer is the final authority.
FAQ
What margins does KDP require for a paperback?
Without bleed: at least 0.25 in on the top, bottom and outside edge, and an inside (gutter) margin of 0.375 to 0.875 in depending on page count. With bleed, the outside margins grow to at least 0.375 in.
What is the gutter on KDP?
The inside margin next to the spine. Thicker books bend more at the binding, so KDP asks for a wider gutter as the page count grows: 0.375 in up to 150 pages, 0.5 in up to 300, 0.625 in up to 500, 0.75 in up to 700 and 0.875 in up to 828.
Which side is the gutter on?
Page 1 is a right-hand page, so odd pages have the gutter on the left and even pages on the right. Mirror your margins (Word: “Mirror margins”) so the gutter is always on the spine side.
Why does KDP say “content outside margins” when my margins look fine?
Usually a page number, header or image sits lower or further out than the body text, or your document was set up for a smaller page count’s gutter. The free check marks the exact pages and lines.
Should I use the minimum margins?
Treat them as the limit, not the target. Text sitting right on the line is legal but looks cramped; our fix keeps at least 0.08 in inside KDP’s margins by default for that reason.