KDP says my text is outside the margins: what it means and how to fix it

If KDP's Print Previewer stops you with a margin problem, the message usually reads something like "text outside margins" or "insufficient gutter". KDP doesn't publish the exact on-screen wording, but its help page on fixing formatting issues has a section on content outside the margins, and the cause is nearly always one of a handful of small things.

A margin is the blank border between your text and the edge of the page. The gutter is the inside margin, the one next to the spine. Books need a bigger gutter than outside margin, because part of the inside of every page disappears into the binding, and the thicker the book, the more disappears.

KDP's minimum margins

As at 4 October 2026, KDP asks for at least 0.25 inches (6.4 mm) at the top, bottom and outside edge of every page. If your book uses bleed (pictures running off the edge of the page), that rises to 0.375 inches (9.6 mm).

The inside margin depends on your page count:

An "insufficient gutter" problem usually comes from setting the inside margin early, when the book was 140 pages, then adding chapters, front matter or a bigger font until it reached 160. The book moved into the next row of the table, but the margin didn't move with it.

What usually pushes text outside

KDP's help lists the usual suspects:

• Page numbers or headers sitting too close to the edge.
• A stray text box, often an empty one, dragged into the margin.
• Spaces at the end of lines or paragraphs.
• Italic letters that lean out past the edge of the text.

How to fix it in Word

1. Check your page count, then find your row in the table above.
2. Go to Layout > Margins > Custom Margins. Under Pages, choose Mirror margins, so the Inside box is always the edge next to the spine.
3. Set Inside to at least your figure. Word adds the Gutter box on top of Inside, so if you use both, the two together must reach the figure. Leaving Gutter at 0 keeps it simple.
4. Set Top, Bottom and Outside to at least 0.25 in (0.375 in if your book has bleed).
5. On the Layout tab of the same box, set the Header and Footer "From edge" distances to at least the same minimum, so page numbers can't sit in the strip KDP doesn't allow.
6. Turn on the ¶ button (Home tab) to show hidden marks. Look for empty text boxes, spaces at line ends, and anything sitting outside the text area. Delete them.
7. Save as PDF again and re-upload.

If your page count changes later, check the table again before you upload.

Using a designer, InDesign, Affinity or Canva? Set the inside and outside margins in the document setup from the table above, check that no text frame, page number or running header sits beyond them, and export again.

Lulu and IngramSpark

Lulu treats margins as recommendations rather than a hard line. It asks for a 0.5 in safety margin around all content and at least 0.2 in of gutter, and recommends a wider inside margin as the book gets thicker:

IngramSpark recommends at least 0.5 in on every side, page numbers included, and says its printing can vary by 1/16 in. It doesn't publish a gutter table by page count.

If you print the same book with more than one company, use the biggest margin any of them asks for. A slightly roomier page reads better anyway.

Check before you upload

Bervet's free spine width calculator also checks print PDFs, including your margins against each printer's numbers. The check runs in your browser and nothing is uploaded; checking a PDF needs a free Bervet account. If you haven't settled on a trim size yet, book trim sizes lists what each printer offers.