A printed proof arrives and a thin white margin runs along one edge of an interior page. The artwork was meant to fill the page. On screen it did. In print, a sliver of paper shows through. The fix is bleed — but bleed is one of the most confusingly named decisions in book production, and one of the most common reasons interior files come back from KDP marked "does not meet our requirements". This note is the explanation that should appear next to the setting.
What bleed is, mechanically
Books are printed on sheets larger than the finished page. After printing, the sheets are stacked, bound and then trimmed to the final size with a guillotine blade. The blade is not precise to the millimetre. It is precise to within roughly a sixteenth of an inch (about 1.6 mm), and that tolerance has to live somewhere.
If your artwork ends exactly at the trim line, two things can happen:
- The blade cuts a hair on the artwork side. A thin strip of artwork is lost.
- The blade cuts a hair on the paper side. A thin strip of unprinted paper remains, showing as a white line at the edge of the page.
The second case is what produces the unhappy proof. The fix is to extend the artwork past the trim line by a small margin, so the blade can land anywhere within its tolerance window and still cut through inked area. That extension is bleed.
KDP requires 0.125 in (3.175 mm) of bleed on every outer edge of any interior that bleeds — that is, any interior whose artwork is meant to run to the edge of the finished book.
When you need bleed and when you don't
Bleed is a per-book decision in KDP's terms, not a per-page decision. The whole interior is either set up for bleed, or it is not.
You don't need bleed if
- Your interior is text first, with no full-page images, no full-page colour panels, no decorative bars running to the edge.
- All illustrations sit comfortably inside the printable area with white margins around them.
- This is most novels, most non-fiction with text and inset images, and most poetry collections.
A non-bleed interior is the cleaner default. KDP's no-bleed minimum margin is 0.25 in on the outer, top and bottom edges. The cover formula is unchanged. There is nothing to extend past the trim line.
You need bleed if
- Photographs run to the edge of the page — cookbooks, photo books, art books, illustrated children's titles.
- Full-page colour panels, decorative bars or background washes touch the trim.
- A chapter opener has full-bleed artwork behind the title.
- The interior is a low-content book — a journal, planner or workbook — where ruled or dotted patterns extend to the edge of the page.
If any of those describes one or more pages, the whole interior is set up with bleed enabled. You cannot mix bleed and non-bleed pages in a single file.
What changes when bleed is on
Two things change in the interior file. One thing does not change in the cover.
The page is physically larger in the PDF
A 6 × 9 in trim with bleed produces a PDF where each page is 6.25 × 9.25 in. The extra 0.125 in on every side is the bleed margin. Artwork meant to run to the edge is drawn out to that larger boundary; the trim happens later, at the printer.
The safe margins move inward
KDP enforces stricter margins on bleed interiors. The minimum outer, top and bottom margin grows from 0.25 in (no bleed) to 0.375 in (with bleed). The gutter — the inner margin against the spine — scales with page count regardless of bleed:
| Page count | Gutter (in) |
|---|---|
| 24 – 150 | 0.375 |
| 151 – 300 | 0.500 |
| 301 – 500 | 0.625 |
| 501 – 700 | 0.750 |
| 701 – 828 | 0.875 |
The wider outer margin on bleed pages exists because text or non-bleeding artwork that sits close to the trim line risks being cut by the same blade tolerance that makes bleed necessary. Keeping content at least 0.375 in inside the trim line guarantees it survives.
The cover bleed stays the same
A common point of confusion: bleed on the interior does not change the cover's bleed. The cover always requires 0.125 in of bleed all round, on every paperback, whether the interior bleeds or not. The interior bleed decision is purely about what happens inside the book.
How bleed flows through a file
In any layout tool, bleed shows up at three points:
- Document setup. You declare the trim size (6 × 9 in) and a bleed amount (0.125 in). The tool draws a bleed guide outside the trim guide.
- Layout. Anything meant to run to the edge is dragged to the bleed line, not the trim line. Text and important graphics are kept inside the safe margin.
- Export. When exporting to PDF, you tick "Include bleed" — sometimes called "Use document bleed" or "Bleed marks". The resulting PDF has a larger page size that includes the bleed margin.
Skip any of those three steps and the bleed setting doesn't survive into the file. KDP receives a 6 × 9 in PDF where you thought you were uploading a bleed-included 6.25 × 9.25 in file, and the cover that was sized for a bleeding interior is now misaligned against a non-bleeding one.
Common mistakes
A short list of the recurring bleed errors, with the symptom and the fix:
- Bleed declared but not exported. The document has bleed guides. The export doesn't include them. Result: a normal-sized PDF, KDP rejects it because the artwork stops at the trim line. Fix: re-export with bleed included.
- Bleed exported but not used. The PDF is 6.25 × 9.25 in but no artwork actually extends past the 6 × 9 in trim line. The print is fine; nothing breaks; but the file is technically misconfigured. Fix: only enable bleed on the interior if at least one page actually uses it.
- Mixed bleed and non-bleed pages. Some pages extend artwork to the edge; others stop short. KDP sees inconsistent edge treatment. Fix: treat the whole interior as one decision — bleed on every page that touches the edge, or none.
- Text inside the bleed area. A page number or running header was placed in the bleed margin by mistake. The blade trims it off. Fix: keep all text at least 0.375 in inside the trim line for bleed interiors, 0.25 in for non-bleed.
The cleaner mental model
Think of bleed as a binary decision made once per book:
- "My interior is text first, with maybe some images inset on the page." → No bleed. Default margins. PDF size matches the trim.
- "My interior has artwork that touches the edge of the page anywhere." → Bleed on. Wider safe margins. PDF is 0.25 in wider and taller than the trim.
You do not need to set bleed per page, per chapter, or per image. The whole interior is either set up for bleed or it isn't.
Where Folio Format fits
Folio Format treats bleed as a single decision at the book level. The page size, safe margins and export PDF dimensions follow automatically. The export pre-flight checks that anything in the bleed area really does extend past the trim line, and that nothing important — page numbers, running heads — is sitting where the blade will cut. The arithmetic above is still the same arithmetic; the studio handles the consistency.
Last checked 22 May 2026. Always confirm current Amazon KDP and IngramSpark specifications before uploading final files. Folio Format is designed to help users export KDP-ready files and catch common publishing issues before upload; it makes no claim about platform acceptance.