Amazon KDP Requirements — The Complete File Spec Guide
Every file format, margin rule, and metadata requirement for publishing on Amazon KDP. Updated for 2026.
Two paths to publish
Amazon KDP supports two publishing formats: print (paperback and hardcover) and ebook (Kindle). Each path has its own file requirements, and many authors publish both from the same KDP account.
For print interiors, KDP accepts PDF files. For ebook interiors, KDP accepts EPUB (preferred) and KPF files. DOC and DOCX uploads are technically supported for ebook but are not recommended — the conversion quality is inconsistent and you lose control over formatting.
This guide covers every specification for both paths, so you can submit files that pass validation on the first upload.
Print interior requirements
These specifications apply to both paperback and hardcover interiors. Your PDF must match every requirement below, or KDP will reject the file during the review process.
File format
PDF (PDF/A or PDF 1.4+)
Encrypted or password-protected PDFs are not accepted.
Page size
Must exactly match selected trim size
If you selected 5.5″ × 8.5″, your PDF pages must be exactly that size.
Color space
Grayscale, sRGB, or CMYK
Use grayscale for black-and-white interiors. Use sRGB or CMYK for color interiors.
Font embedding
All fonts must be embedded
No system font references. Every glyph used must be included in the PDF.
Image resolution
300 DPI minimum
Images below 300 DPI will trigger a warning or outright rejection.
Bleed
0.125″ on all sides (if needed)
Only required if content extends to the page edge. Most novels do not need bleed.
Page count
Even number, 24–828 pages
Paperback range. Premium color maximum is 550 pages. Odd page counts are rejected.
Crop marks
Not accepted
Do NOT include crop marks, registration marks, or color bars in your PDF.
Transparency
Must be flattened
All transparent elements must be flattened before upload. Unflattened transparency causes rendering errors.
KDP margin requirements
Minimum inside (gutter) margin
KDP sets the minimum inside margin based on your total page count. The gutter must be wide enough for the binding glue to hold without cutting into your text block.
| Page Count | Minimum Inside Margin |
|---|---|
| 24–150 pages | 0.375″ |
| 151–300 pages | 0.5″ |
| 301–500 pages | 0.625″ |
| 501–700 pages | 0.75″ |
| 701–828 pages | 0.875″ |
Outside, top, and bottom margins
KDP requires a minimum of 0.25″ on the outside, top, and bottom edges for books without bleed. With bleed enabled, the outside minimum increases to 0.375″.
Ebook requirements
Kindle ebooks are reflowable — the reader controls font size, margins, and line spacing. Your file provides the content structure, and the Kindle device or app handles the layout.
File format
EPUB (preferred), KPF, or DOC/DOCX
EPUB gives you the most control. DOC/DOCX uploads are converted by Amazon and often produce formatting errors.
EPUB version
EPUB 2 or EPUB 3
Both versions are accepted. EPUB 3 supports more features but EPUB 2 has wider compatibility.
Cover image
Min 1000 × 625 px, ideal 2560 × 1600 px
JPEG or TIFF. The ideal ratio is 1.6:1 (height to width).
DRM
Optional
Selected during the publishing setup process, not embedded in your file.
Table of contents
Required — HTML TOC
Must include an HTML-based table of contents, not NCX-only. Kindle uses the HTML TOC for navigation.
Font embedding
Supported but optional
Kindle devices may override embedded fonts with the reader's preferred typeface.
Images
JPEG or PNG
Inline images are supported. Keep total file size under 650 MB.
Cover requirements
Print cover
- Format: PDF, single page containing front cover + spine + back cover
- Resolution: 300 DPI minimum
- Bleed: 0.125″ on all sides of the full cover wrap
- Color space: CMYK recommended, sRGB accepted
- Spine width: Calculated from page count × paper thickness
Spine width calculation
White paper: page count × 0.002252″
Cream paper: page count × 0.0025″
Example: a 300-page book on cream paper has a spine width of 300 × 0.0025 = 0.75″. KDP requires a minimum of 79 pages before spine text is allowed.
Ebook cover
- Format: JPEG or TIFF
- Ideal size: 2560 × 1600 pixels (1.6:1 height-to-width ratio)
- Minimum size: 1000 × 625 pixels
- Maximum file size: 50 MB
Metadata requirements
KDP collects metadata during the publishing setup. This information determines how your book appears in the Kindle Store and in search results. Getting it right affects discoverability.
| Field | Details |
|---|---|
| Title & subtitle | Must match the text on your cover. Subtitle is optional but improves discoverability. |
| Author name | Must match your KDP account name or a registered pen name. |
| Description | Up to 4,000 characters. Supports basic HTML (<b>, <i>, <br>, <p>). |
| Categories | Up to 3 BISAC categories. Choose the most specific categories that fit your book. |
| Keywords | Up to 7 keyword phrases, separated. Do not duplicate words already in your categories. |
| ISBN | Optional. KDP assigns a free ISBN, or you can provide your own. KDP-assigned ISBNs are Amazon-exclusive. |
| Language | The primary language of the book content. |
| Publication date | Set automatically on first publish. Can be set to a future date for pre-orders. |
Common rejection reasons
These are the most common reasons KDP rejects uploaded files. Check your manuscript against this list before uploading to avoid delays.
- Inside margin too narrow for page count. The gutter margin must increase as page count grows. A 300-page book needs at least 0.5″ inside margin.
- Page size doesn't match selected trim size. Your PDF page dimensions must be an exact match — not "close enough."
- Fonts not embedded in PDF. Every font used in the document must be embedded. System font references will fail.
- Odd page count. Print books must have an even number of pages. Add a blank page at the end if necessary.
- Content extends into margin area. Text, images, or page numbers that fall inside the minimum margin zone will be flagged.
- Low-resolution images. Any image below 300 DPI will generate a quality warning. Severely low-resolution images cause rejection.
- Cover spine width doesn't match page count. The spine must be calculated from your actual page count and paper type.
- Transparency not flattened. Unflattened transparent layers in the PDF can cause rendering artifacts during printing.
- File too large. Maximum file size is 650 MB for both print and ebook uploads.
- Missing or malformed table of contents in EPUB. Kindle requires a working HTML-based table of contents for navigation.
Related resources
Trim Size Guides
Margins, page counts, and specs for every popular book size on KDP and IngramSpark.
View guides →KDP Book Calculator
Enter your word count and see pages, spine width, printing cost, and royalty estimates.
Open calculator →Formatting Checklist
Step-by-step checklist to verify your manuscript meets every KDP requirement.
View checklist →How to Format a Book for KDP
Complete formatting walkthrough from manuscript to upload-ready PDF.
Read article →Fixing KDP Rejections
Diagnose and fix the most common KDP file errors so you can publish without delays.
Read article →IngramSpark Requirements
How IngramSpark specs differ from KDP — a side-by-side comparison for wide distribution.
View guide →FAQ
What file format does KDP accept for print interiors?
Does KDP require an ISBN?
What is the maximum page count for a KDP paperback?
Can I publish a hardcover on KDP?
What DPI do images need to be for KDP?
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