Amazon KDP Formatting Requirements 2026
What file format does KDP require for print?
A print-ready PDF with all fonts embedded, images at 300 DPI minimum, CMYK colour profile for colour interiors, correct margins for your trim size and page count, and 0.125 inch bleed only if content reaches the page edge. Never submit a Word document directly for print.
Book formatting serviceHow do I calculate KDP spine width?
White paper: (page count × 0.002252) + 0.06 inches. Cream paper: (page count × 0.0025) + 0.06. Always calculate from your final locked page count after interior formatting is complete — even a 10-page change invalidates the cover file.
See worked examplesWhat margins does Amazon KDP require?
Inside (gutter) margin depends on page count. Up to 150 pages: 0.375 inch. 151–300 pages: 0.5 inch. 301–500 pages: 0.625 inch. 501–700 pages: 0.75 inch. Outside, top and bottom: 0.25 inch minimum. Always use mirror margins.
Full margin tableWhat is the difference between KDP and IngramSpark formatting?
Both require print-ready PDFs with embedded fonts, but differ on bleed requirements, spine width calculation, colour profile handling and cover PDF construction. If publishing to both, format to the stricter IngramSpark specification — those files also pass KDP without modification.
KDP vs IngramSpark spec comparisonIn This Guide
- Why formatting matters more than most authors expect
- Print interior PDF requirements
- KDP trim sizes — full 2026 table
- Margin requirements by page count
- Bleed settings: when you need it and when you don't
- Spine width formula with worked examples
- Cover PDF requirements
- EPUB and Kindle eBook requirements
- Formatting software compared
- Most common KDP formatting errors
- IngramSpark vs KDP formatting differences
- Pre-submission checklist
- Frequently asked questions
Interior formatting errors are the single most common cause of KDP file rejection, launch delays and poor reader reviews. A book that fails the automated KDP file check cannot go live. A book that passes the check but has formatting errors invisible in the digital preview shows those errors the moment it is physically printed. Neither outcome is recoverable without reformatting and re-uploading from scratch.
This guide covers every KDP specification for 2026 — trim sizes, margin tables, bleed settings, spine width calculations and EPUB standards — with the precision needed to pass the KDP automated check on the first submission. If you want professional formatting handled by a specialist, Columbia Publication's Amazon KDP publishing service includes interior formatting preflighted against KDP and IngramSpark specifications before every submission.
Why Formatting Matters More Than Most Authors Expect
The formatting of a book determines the reading experience before a single word has been processed. Readers encountering an improperly formatted book — inconsistent line spacing, misaligned headings, incorrect page numbering, chapters starting mid-page — make an immediate judgement: unprofessional. That judgement is not recoverable by the quality of the writing.
Formatting errors affect commercial performance directly. The most common critical reader reviews for self-published books cite formatting problems: text disappearing into the spine, inconsistent font sizes between chapters, images printing pixelated, widows left at the top of pages. These reviews appear on the Amazon listing indefinitely and suppress future sales permanently.
What are the print interior PDF requirements?
KDP accepts PDF files for print interiors. The following technical specifications are mandatory. KDP's automated file checker tests for most of these on upload; those it misses become quality problems visible only in the printed book.
- File format: PDF — PDF/X-1a recommended, PDF/X-4 accepted
- Fonts: All fonts embedded without exception — unembedded fonts fail the file check or print with substitutions
- Image resolution: 300 DPI minimum at the final placed size in the layout, not the original file size
- Colour mode for B&W interiors: Greyscale images only — RGB images produce unexpected grey tones in print
- Colour mode for colour interiors: CMYK for all images — RGB images produce colour shifts
- Bleed: 0.125 inch on all four sides only if any content extends to the page edge
- Page dimensions: Must match the trim size selected on KDP exactly (plus bleed if used)
- Transparency: Flatten all transparency before exporting the final PDF
- Max file size: 400 MB for B&W; 650 MB for colour
The page dimensions in your PDF must match the trim size you select on KDP precisely. Set up the document at the correct trim size first, then select the matching size on KDP. Any mismatch causes rejection.
KDP Trim Sizes Full 2026 Table
The trim size is the physical dimension of the finished printed book. Choose your trim size before starting any formatting work — changing it after the interior is formatted requires resetting all margins, reflowing all text and recalculating the spine width from scratch.
| Trim Size | Best Used For | Min Pages | Max Pages |
|---|---|---|---|
| 5 × 8 inches | Compact fiction, poetry, short non-fiction | 24 | 828 |
| 5.06 × 7.81 inches | Compact trade paperback | 24 | 800 |
| 5.25 × 8 inches | Mass market fiction alternative | 24 | 800 |
| 5.5 × 8.5 inches | Standard trade, literary fiction, shorter non-fiction | 24 | 800 |
| 6 × 9 inches Most popular | Non-fiction, business, self-help, memoir, biography | 24 | 828 |
| 6.14 × 9.21 inches | Larger trade, academic | 24 | 800 |
| 7 × 10 inches | Textbooks, educational, illustrated non-fiction | 24 | 800 |
| 7.44 × 9.69 inches | Academic textbooks, reference | 24 | 800 |
| 8 × 10 inches | Illustrated books, journals, activity books | 24 | 800 |
| 8.5 × 8.5 inches | Picture books, square illustrated books | 24 | 590 |
| 8.5 × 11 inches | Workbooks, large-format non-fiction, planners | 24 | 590 |
| 8.27 × 11.69 (A4) | Academic, European market | 24 | 590 |
The 6×9 trim is the default for most adult non-fiction — the format readers associate with professionally published books in this category. For fiction, 5.5×8.5 or 5×8 are common. See the self-publishing cost guide for how trim size affects printing costs and royalties.
Margin Requirements by Page Count
KDP sets minimum margin requirements based on page count because longer books need a larger gutter — the inside margin nearest the spine — to remain readable when open. If the gutter is too narrow, text disappears into the binding.
| Page Count | Inside (Gutter) Min | Outside Min | Top Min | Bottom Min | Recommended Gutter |
|---|---|---|---|---|---|
| 24 – 150 pages | 0.375 inch | 0.25 inch | 0.25 inch | 0.25 inch | 0.5 inch |
| 151 – 300 pages | 0.5 inch | 0.25 inch | 0.25 inch | 0.25 inch | 0.625 inch |
| 301 – 500 pages | 0.625 inch | 0.25 inch | 0.25 inch | 0.25 inch | 0.75 inch |
| 501 – 700 pages | 0.75 inch | 0.25 inch | 0.25 inch | 0.25 inch | 0.875 inch |
| 701 – 828 pages | 0.875 inch | 0.25 inch | 0.25 inch | 0.25 inch | 1.0 inch |
Bleed Settings When You Need It and When You Don't
Bleed is the extension of design elements beyond the trim line of the page. It prevents a thin white border appearing at the page edge if the printer cuts fractionally outside the trim line. The KDP bleed requirement is 0.125 inch (3.2mm) on all four sides.
You need interior bleed if: any image, background colour or design element extends to the physical edge of the page. Full-page photographs, coloured backgrounds and children's picture books with full-bleed illustrations all require bleed.
You do not need interior bleed if: your book is text-only with white margins, or all images are placed inside the margin boundary and do not touch the page edge. Most business, self-help, non-fiction and fiction books have no interior bleed requirement.
Spine Width Formula with Worked Examples
The spine width depends on page count, paper type and trim size. Always calculate from the final confirmed page count — never an estimate. Building the cover before the interior is complete is the most common cause of spine width errors and cover rejections.
KDP Spine Width Formulas
White paper: spine width = (page count × 0.002252) + 0.06 inches Cream paper: spine width = (page count × 0.0025) + 0.06 inches Colour paper: spine width = (page count × 0.002347) + 0.06 inchesExample — 250 pages, white paper (6×9)
Example — 380 pages, cream paper
Once you have the spine width, the total cover PDF width is: back cover width + spine width + front cover width + (0.125 × 2) for bleed. See Columbia Publication's cover design service for KDP-ready cover production with spine width calculation included.
What are the cover PDF requirements?
The cover is a separate PDF from the interior, containing the front cover, spine and back cover as one flat file. KDP's automated checker tests cover files for dimension accuracy, resolution and colour profile. A failed cover check requires recalculating dimensions and rebuilding the file from scratch.
- File format: PDF with all fonts embedded
- Colour profile: CMYK — RGB covers produce unpredictable colour shifts in print
- Resolution: 300 DPI minimum at final print size; 600 DPI recommended
- Bleed: 0.125 inch on all four sides — always required
- Safe zone: 0.25 inch inside trim line on all sides — all text and logos must stay inside
- Spine text: Only include if spine is at least 0.0625 inch wide — thinner spines cannot accommodate readable text
- ISBN barcode area: Leave lower right of back cover clear (approximately 2×1.2 inches) for the barcode KDP adds automatically
- Total cover width: (trim width × 2) + spine width + (0.125 × 2)
- Total cover height: trim height + (0.125 × 2)
What are EPUB and Kindle eBook requirements?
Kindle eBooks use different requirements from print. KDP accepts multiple formats for eBook upload but EPUB 3 produces the most consistent results across all Kindle devices, Kindle apps and the web-based Cloud Reader.
| Format | Accepted | Recommended | Notes |
|---|---|---|---|
| EPUB 3 Best | Yes | Yes | Best compatibility across all Kindle devices and apps. Supports fixed layout for picture books. |
| EPUB 2 | Yes | Acceptable | Older standard. Works for plain text books but lacks EPUB 3 features. |
| DOCX | Yes | No | Converted automatically by KDP with inconsistent results. Only acceptable for very simple plain text. |
| MOBI | Yes | No | Legacy Kindle format, deprecated in favour of EPUB. KDP converts internally anyway. |
| HTML | Yes | No | Functional for plain text but inferior to a properly structured EPUB. |
| Limited | No | Poor results on small screens. Not recommended for eBook upload. |
EPUB technical requirements:
- Maximum file size: 650 MB including all embedded images
- Cover image: Separate JPEG, minimum 1,000×625 pixels; 2,560×1,600 recommended
- Images: 150–300 DPI recommended for screen display
- Fonts: Embed all custom fonts in the EPUB file
- Table of contents: Both a logical nav TOC and a visible HTML TOC recommended
- Fixed layout: Use for picture books and content where page layout must be preserved exactly
Dedicated formatting software like Vellum (Mac only, $250 one-time) and Atticus (Windows and Mac, $147 one-time) produces more reliable KDP-compliant EPUB files than Word. For a single title, professional book formatting by Columbia Publication is often more cost-effective than learning the software.
Which formatting software should you choose?
The right software depends on your goals, technical comfort level and the complexity of your book.
Vellum
- Beautiful, professional EPUB and print PDF output
- Very easy to use — minimal learning curve
- Excellent for fiction and straightforward non-fiction
- Generates eBook and print from a single source
- Mac only — no Windows version
- Limited control over complex layouts and tables
- Not suitable for textbooks or illustrated books
Atticus
- Works on both Windows and Mac
- Purpose-built for KDP and eBook output
- Good value for authors publishing multiple books
- Built-in writing environment alongside formatting tools
- Less design flexibility than InDesign
- Fewer print style options than Vellum
- Relatively new product, some features still developing
Adobe InDesign
- Professional standard used by commercial publishers
- Full control over every typographic and layout detail
- Best option for complex layouts and illustrated books
- Exports print-ready PDFs that pass KDP check reliably
- Significant learning curve for non-designers
- Monthly subscription adds up for occasional users
- EPUB export requires additional configuration
Microsoft Word
- Most authors already have it installed
- Acceptable for simple eBook upload only
- KDP templates available for basic formatting
- Direct print upload to KDP not recommended
- Inconsistent PDF export across OS versions
- No control over professional typographic details
- Hidden styles and auto-formatting cause silent errors
What are the most common KDP formatting errors?
These errors most frequently cause KDP file rejections or produce quality problems in the published book. Most are invisible in Word and in KDP's on-screen preview — but visible and permanent in the physical printed copy.
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Unembedded fonts Fonts not embedded in the PDF cause the KDP file check to fail, or produce font substitution where your chosen font is replaced with a system default. Use Press Quality PDF export settings and verify embedding with Acrobat's preflight before uploading.
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RGB images in a print interior RGB images in a B&W print file produce unexpected grey tones. RGB images in a colour print file produce colour shifts. Convert all images to Greyscale for B&W interiors and CMYK for colour interiors before placing in the layout.
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Wrong spine width on the cover Using an estimated or early-draft page count to calculate spine width produces a cover that does not match the book. Always finalise interior formatting and lock the page count before building the cover PDF.
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Margins not set as mirror margins Print books require mirror margins so the gutter always sits on the spine side. Identical margins on all four sides produce a book where alternating spreads have a narrow inner margin and text disappears into the binding.
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Low-resolution images below 300 DPI Images that look sharp on screen can print with visible pixelation. Check resolution at the final placed size in the layout — an image at 300 DPI in its source file may be below 300 DPI when scaled up in the layout.
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Chapters not starting on right-hand pages Commercial publishing convention places new chapters on right-hand (odd-numbered) pages. Chapters starting on any page signal unfamiliarity with publishing standards. Use section breaks set to Odd Page in your layout software.
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Cover text placed outside the safe zone Content between the trim line and the 0.25 inch safe zone risks being cut off during printing. The bleed area is for backgrounds and images only — never for title, author name or logos.
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Page numbers in the gutter or too close to trim Page numbers placed too close to the spine or the outer edge may be clipped or unreadable. Keep all page numbers at least 0.25 inch from every trim edge, within the safe zone.
IngramSpark vs KDP Formatting Differences What Changes Between Platforms
Most professionally self-published books are set up on both Amazon KDP and IngramSpark simultaneously — KDP for Amazon sales, IngramSpark for global bookshop and library distribution. The two platforms share most formatting requirements but differ on a handful of specification details that cause file rejections when authors assume the platforms are identical.
The practical rule: format to the IngramSpark specification where the two diverge. IngramSpark files built to their stricter requirements also pass KDP's automated check without modification, meaning you produce one set of files that works across both platforms. See the full KDP vs IngramSpark distribution guide for platform setup detail.
| Specification | Amazon KDP | IngramSpark | Use Which? |
|---|---|---|---|
| Cover bleed | 0.125 inch all sides | 0.125 inch all sides | Either — identical |
| Interior bleed (full bleed content) | 0.125 inch all sides | 0.125 inch all sides | Either — identical |
| Spine width calculation | Platform-specific formula per paper type | Slightly different formula — use IngramSpark's cover template calculator | Build separate covers — spine widths differ slightly |
| Colour profile (interior) | Greyscale for B&W; CMYK for colour | Greyscale for B&W; CMYK for colour | Either — identical |
| Image resolution | 300 DPI minimum | 300 DPI minimum; 600 DPI recommended for covers | Format to 300 DPI interior, 600 DPI cover — passes both |
| ISBN requirement | Free KDP ISBN available (Amazon-only) | Purchased ISBN required (your own) | Buy your own ISBN from Bowker (US) or Nielsen (UK) — works on both |
| Returns policy (bookshop orders) | No returns option available | Returnable option required by most bookshops | Set IngramSpark to returnable for full bookshop access |
| Wholesale discount | Set within KDP (no bookshop ordering) | Minimum 40% discount for bookshop ordering | Set IngramSpark to 40%+ for retail orders to work |
The spine width difference is the most practically significant. IngramSpark uses its own cover template calculator which produces slightly different dimensions than KDP's formula for the same book. The result: the interior PDF is identical across both platforms, but the cover PDF must be built separately for each — same design, different dimensions. Columbia Publication's Amazon publishing service prepares separate preflighted cover files for both platforms as standard.
Pre-Submission Checklist Run This Before Every KDP Upload
Run through this checklist before submitting any file to KDP. Every item catches a real error that authors commonly discover only after a rejection notification or, worse, after the book is live and readers have reported the problem in reviews. The checklist takes five minutes. Fixing a live formatting error takes days and leaves a trail in the version history that some readers notice.
Interior PDF
- ✓All fonts embedded — verify with Acrobat preflight or preflight tool in InDesign
- ✓Page dimensions match the trim size selected on KDP exactly
- ✓Mirror margins enabled — gutter on spine side of every page
- ✓Gutter meets the minimum for your final page count
- ✓All images at 300 DPI minimum at the placed size in the layout
- ✓Images are Greyscale (B&W interior) or CMYK (colour interior)
- ✓All transparency flattened before PDF export
- ✓Chapter openings on right-hand (odd-numbered) pages
- ✓Page numbers absent from front matter and chapter opening pages
- ✓Bleed set to 0.125 inch only if content reaches the page edge
- ✓File size under 400 MB (B&W) or 650 MB (colour)
Cover PDF
- ✓Spine width calculated from the final locked page count using the correct formula
- ✓Total cover width = (trim width × 2) + spine width + (0.125 × 2)
- ✓Total cover height = trim height + (0.125 × 2)
- ✓Colour profile is CMYK throughout
- ✓Resolution 300 DPI minimum at print size; 600 DPI recommended
- ✓0.125 inch bleed on all four sides
- ✓All text and logos within the 0.25 inch safe zone
- ✓Back cover lower right clear for ISBN barcode (2 × 1.2 inches)
- ✓Spine text only included if spine is 0.0625 inch or wider
- ✓All fonts embedded in the cover PDF
- ✓Transparency flattened before export
Frequently Asked Questions About KDP Formatting
Which related publishing guides should you use?
Amazon KDP Complete Guide 2026
Account setup, royalties, categories, keywords, KDP Select decision and IngramSpark setup — every stage explained. Includes royalty calculator.
Read the guideAmazon KDP Publishing Service
Done-for-you KDP formatting, cover design, category research and global distribution. Files preflighted before submission.
View serviceKDP-Ready Cover Design
Covers designed to KDP thumbnail specifications with correct CMYK files, spine width calculation and bleed setup included.
View serviceBook Formatting Service
Professional interior formatting for KDP and IngramSpark. Print-ready PDFs and EPUB to current platform specifications.
View serviceKDP vs IngramSpark: Using Both
Why most professionally self-published books are set up on both platforms simultaneously and how global distribution works.
Read the guideSelf-Publishing Cost Guide
Real costs for every production stage including formatting and cover design, with honest breakdowns at every budget level.
See the numbers