KDP Formatting Requirements: The Definitive Reference So You Never Get a Rejection Email Again

There’s a special kind of despair that comes with receiving a KDP rejection email the day before your planned launch. You stare at phrases like “margin violation” and “bleed mismatch” and wonder how something so technical ended up being your problem. You’re a writer. You didn’t sign up for production engineering.

But here we are. Amazon KDP has specific formatting requirements for both print and ebook, and they’re enforced by an automated checker that has all the empathy of a parking meter. Miss a specification, and your file bounces. No exceptions, no “close enough,” no human reviewer who’ll squint at your margins and decide they’re probably fine.

I’ve compiled every requirement that matters into one reference — sourced directly from KDP’s official documentation and submission guidelines. Bookmark this page. You’ll need it.

Print Book Requirements

File Format

Submit a PDF with all fonts embedded. This is non-negotiable. A PDF with missing font embedding will either fail the automated check or print with substituted fonts that look nothing like your design. If you’re using book formatting software, font embedding is typically automatic. If you’re exporting from Word, verify embedding in your PDF export settings (Print → Save as PDF → check “Embed fonts”).

Do not submit: .docx, .pages, or any non-PDF format for print. The conversion is unreliable and produces formatting artifacts. Do not include: crop marks, trim marks, bookmarks, comments, annotations, or metadata in your PDF. KDP’s checker flags all of these.

Trim Sizes

KDP supports a range of trim sizes. The most commonly used, according to industry guides:

5″ × 8″ — Compact fiction, mass market paperback feel. Good for genre fiction, poetry, novellas.

5.5″ × 8.5″ — Slightly roomier. Popular for general fiction and lighter nonfiction.

6″ × 9″ — The most common US trade paperback size. Standard for nonfiction, business, self-help, memoir, and literary fiction.

8.5″ × 11″ — Workbooks, activity books, cookbooks, and specialty formats.

Your PDF page size must exactly match your chosen trim size. If your trim is 6″ × 9″ and your PDF is letter-size (8.5″ × 11″), the file will be rejected.

Margins and Gutters

Margin requirements vary by page count — specifically, the inside margin (gutter) increases as page count grows because thicker books curve more at the spine. Based on KDP’s specifications for a 6″ × 9″ trim:

24–150 pages: Inside (gutter) margin minimum 0.375″

151–300 pages: Inside margin minimum 0.75″

301–500 pages: Inside margin minimum 0.875″

501–700 pages: Inside margin minimum 1.0″

701+ pages: Inside margin minimum 1.125″

Outside, top, and bottom margins have a minimum of 0.25″, though professional formatters typically use 0.5″ or more for comfortable reading. These are minimums — your print formatting should use values that produce a comfortable reading experience, not just the bare minimum that passes validation.

Bleed

Bleed applies when your interior contains images or elements that extend to the page edge. If your book is text-only, you don’t need bleed. If even one page has a bleeding element, the entire file must be set up for bleed.

With bleed, extend content 0.125″ (3.2mm) beyond the trim line on top, bottom, and outside edges. Your PDF page size increases accordingly: a 6″ × 9″ trim with bleed becomes 6.125″ × 9.25″.

The bleed setting you select during KDP setup must match your file. Selecting “Bleed” with a non-bleed file (or vice versa) is one of the most common rejection triggers.

Images

Minimum resolution: 300 DPI. Images below 200 DPI are flagged by the automated checker. Images between 200–300 DPI may pass the check but will show visible quality degradation in print. For black-and-white interiors, use grayscale images. For color interiors, RGB or CMYK are both accepted.

Ebook (Kindle) Requirements

Kindle formatting requirements are less rigid than print but have their own specifics. See the full Kindle formatting guide for a step-by-step walkthrough.

Recommended format: EPUB. KDP also accepts .doc/.docx, but the conversion process introduces formatting artifacts. Use ebook formatting software that exports clean EPUB directly.

Cover image: Minimum 1,000 pixels on the shortest side. Recommended: 2,560 × 1,600 pixels (1.6:1 aspect ratio).

Table of contents: Both an HTML TOC page and a logical (NCX/NAV) navigation structure. Missing the logical TOC generates a warning and degrades navigation on Kindle devices.

Fonts: Embedded or web-safe. Don’t rely on proprietary fonts that may not render on all devices.

File size: Matters for royalty calculation on the 70% option. Amazon deducts a delivery fee based on file size (approximately $0.15 per MB in the US). Optimize images to keep file size reasonable without sacrificing quality.

Cover Requirements (Print)

Print covers must include front, spine, and back as a single continuous PDF. The spine width is calculated from page count and paper type — KDP provides a cover calculator for exact dimensions. Bleed of 0.125″ is required on all sides. Critical content must be at least 0.25″ from the cover edge to avoid being trimmed. Barcode area on the back cover must be clear — KDP adds the barcode automatically.

Common Rejection Triggers

Based on KDP’s documentation and their formatting issue guides, the most common file rejections are:

1. Fonts not embedded. The single most common rejection cause. Verify every font is embedded in your PDF.

2. Incorrect page dimensions. Your PDF canvas must match your trim size exactly (plus bleed margins if applicable).

3. Content outside margins. Text or images extending into the gutter or beyond the trim edge without proper bleed setup.

4. Bleed mismatch. Selecting “Bleed” during setup but submitting a file without bleed dimensions (or vice versa).

5. Low-resolution images. Any image below 200 DPI triggers a warning; below 150 DPI often triggers rejection.

Good book formatting software catches all of these before you upload. Storyloft’s export process validates against KDP specifications automatically, flagging issues during formatting rather than during the upload-rejection cycle. That’s the difference between a smooth launch day and a stressful one.

Frequently Asked Questions

What file format does KDP require for print books?

PDF with all fonts embedded. Page dimensions must exactly match your chosen trim size. Do not submit Word documents for print.

What are the KDP margin requirements?

Inside margins vary by page count: 0.375″ for under 150 pages, up to 1.125″ for 700+ pages. Outside/top/bottom minimums are 0.25″, though professional formatters use more.

What is the most common reason KDP rejects files?

Missing font embedding, followed by incorrect page dimensions and content outside margin boundaries.

What resolution do images need for KDP print books?

300 DPI minimum. Below 200 DPI gets flagged; between 200–300 DPI passes but prints with visible quality loss.