The Shadow Quill

Last updated on May 24, 2026

Quick Answer

To format an ebook for KDP, your file needs to be structured as a clean EPUB or a properly styled Word document (DOCX) — not a raw export from your writing software. The most important requirements are consistent paragraph styles, a working linked table of contents, no fixed layouts, and images saved in RGB at 72 dpi or higher. Most authors use dedicated formatting software such as Atticus ($147 one-time) or the free Reedsy Book Editor to handle this process reliably. Uploading a poorly structured file produces conversion errors in KDP’s previewer that range from cosmetic to severe enough to require a complete reformat. 

According to WordsRated, self-published titles account for 31% of all ebook sales on Amazon, making KDP the most competitive ebook marketplace in the world for independent authors.

In that environment, a poorly formatted file does not just create a bad reading experience. It suppresses rank, generates early negative reviews, and costs a book the launch momentum it cannot recover in the first weeks on sale.

Formatting is one of the few publishing costs authors can control directly. Understanding the full cost of self-publishing a book on Amazon puts it in context alongside editing, cover design, and ISBNs — and makes clear why getting the format right the first time matters financially, not just technically.

This guide covers every step required to format an ebook for KDP: the file types KDP accepts, how to prepare your manuscript in Microsoft Word, how dedicated formatting tools handle the process more efficiently, and the formatting errors that most commonly trigger KDP’s content quality flags. By the end, you will have a clear, repeatable process you can apply to every book you publish.

KDP Ebook File Requirements

Before touching your manuscript, understand what KDP actually accepts and what it does with the files you upload. KDP converts your uploaded file into its own internal format (KF8/AZW3) for delivery to Kindle devices and apps. The quality of that conversion depends entirely on how cleanly your source file is structured.

Accepted File Formats

KDP accepts several file types, but they are not equal in terms of output quality. The main options are:

• EPUB — the recommended format. It gives KDP the least to interpret and produces the most predictable output across all Kindle devices and apps.
• DOCX — the second most common submission format. Works well when paragraph and heading styles are set up correctly in Word.
• HTML, RTF, plain text — only appropriate for extremely simple manuscripts with no front matter, images, or special elements.

MOBI was KDP’s native format for many years but Amazon deprecated it in 2022. If you have older tutorials recommending MOBI submission, that guidance is out of date. Do not upload MOBI files to KDP.

What KDP Looks For During Conversion

KDP’s conversion engine checks for a specific set of structural requirements. The most important are:

• A valid linked table of contents — not a typed list of chapter names
• Consistent paragraph and heading styles applied through named styles, not manual formatting
• Properly embedded fonts or a clean fallback
• Images in a supported format (JPEG or PNG) at an appropriate resolution in RGB colour mode

Passing KDP’s automated review does not guarantee a clean reading experience. It means KDP could convert the file. Whether the result looks correct on a Kindle Paperwhite, a Fire tablet, or the iOS Kindle app is a separate question — one you answer by checking the KDP previewer before you publish.

How to Format an Ebook for KDP in Microsoft Word

Word is the starting point for most manuscripts, and a correctly configured Word document produces clean KDP output. The critical word is correctly. A Word file full of manual formatting — bold used as a heading, extra returns used as spacing, tabs used for indentation — will convert badly regardless of how clean the text itself is.

Set Up Your Paragraph Styles

Every paragraph in your manuscript must use a named style from Word’s Styles panel, not direct formatting. The correct setup looks like this:

• Body text — use a single customised Normal style with your preferred font, size, line spacing, and first-line indent set at the style level, not applied manually.
• Chapter titles — must use Heading 1. KDP’s conversion engine reads this to build your ebook’s navigation structure.
• Subheadings — must use Heading 2 or Heading 3 consistently throughout the manuscript.

To indent paragraphs, use the paragraph style’s indent setting — not the Tab key and not the spacebar. Manual indentation breaks on every Kindle device because ebook readers render text dynamically at whatever font size the reader has chosen.

Build a Linked Table of Contents

A typed list of chapter names is not a table of contents for KDP purposes. You need a linked table of contents generated from your Heading styles. In Word, insert this through the References tab using the automatic table of contents generator. KDP reads this as the navigation structure for the ebook and surfaces it through the Go To menu on every Kindle. A missing or broken table of contents is one of the most common quality flags KDP issues on first upload.

Insert Page Breaks Between Chapters

Each chapter must begin on a new page. Insert a proper page break — Ctrl+Enter on Windows, Command+Enter on Mac — at the end of each chapter. Do not use repeated blank lines to push content to the next page. Blank lines convert inconsistently across devices and produce ragged chapter openings that vary depending on the reader’s chosen font size.

Handle Images Correctly

If your ebook contains images, follow these requirements before embedding them:

• Save all images as JPEG or PNG — not TIFF, BMP, or any print format
• Convert images to RGB colour mode — CMYK images do not display correctly on Kindle devices
• Use a minimum resolution of 72 dpi — higher is fine, but file size increases accordingly
• Keep total file size well below KDP’s 650 MB upload limit — large embedded images slow conversion and can cause display issues on older devices

Using Dedicated Formatting Software

Dedicated formatting tools handle the technical requirements described above automatically. For authors publishing more than one or two books, the time saved across a catalog justifies the cost of purpose-built software several times over.

Atticus

Atticus ($147 one-time) is a cross-platform formatting tool built specifically for self-publishers. It runs on both Mac and Windows, which puts it ahead of Vellum for authors on PC. You import your manuscript, apply a theme, and export a KDP-ready EPUB and a print-ready PDF from the same file — without reformatting between the two. The table of contents, chapter breaks, and front matter are all handled automatically. The output passes KDP’s conversion requirements without manual adjustment in the vast majority of cases.

For most self-publishers formatting a standard novel or nonfiction title for KDP, Atticus is the most efficient paid option available. For a full breakdown of how it compares to every other tool on the market, see our best book formatting software for self-published authors comparison.

Reedsy Book Editor

Reedsy Book Editor is a free, browser-based formatting tool that exports clean EPUB and print PDF files. It structures your table of contents automatically, applies consistent chapter formatting, and produces output that passes KDP’s review without configuration. The limitation is customisation — you get a small set of preset styles with almost no ability to modify them. For a first-time author who wants to understand the KDP upload process before spending money on software, Reedsy Book Editor is the right starting point.

Kindle Create

Amazon’s own Kindle Create tool is free and imports Word documents directly. It is designed specifically for KDP submission and produces files that pass Amazon’s conversion requirements by definition. The tradeoff is limited design control and output that looks identical to every other book produced with the default settings. Kindle Create is a viable option for authors with no budget and no interest in interior design, but dedicated tools like Atticus produce more professional results with comparable effort once you have learned the interface.

KDP Ebook Format Comparison

The table below compares the most common approaches to formatting an ebook for KDP by cost, output format, learning curve, and best use case. If you are weighing Atticus against Vellum specifically, our Vellum vs Atticus comparison covers the differences in output quality, pricing, and platform support in full detail.

Method	Cost	Output	Learning Curve	Best For
Atticus	$147 one-time	EPUB + PDF	Low	Most KDP authors, Mac and Windows
Vellum	$199.99–$249.99 one-time	EPUB + PDF	Low	Mac users, design-focused genres
Reedsy Book Editor	Free	EPUB + PDF	Very low	First-time formatters, zero budget
Microsoft Word	Free / included	DOCX (KDP converts)	Medium	Authors with strong Word knowledge
Kindle Create	Free	KPF (Amazon only)	Low	KDP-only, no design requirements
Scrivener	$59.99 one-time	EPUB + PDF + DOCX	High	Authors who write and format in one tool

Common Formatting Mistakes That Fail KDP Review

These are the errors that most frequently cause problems at the KDP upload stage. Each one has a specific fix. Identifying which of these apply to your file before upload saves the time of a failed conversion and a complete reformat.

No Linked Table of Contents

A typed chapter list at the front of your manuscript is not a navigation table of contents. KDP requires a linked NCX or nav structure that allows readers to jump to any chapter from the Kindle menu. In Word, use the References tab to generate this automatically from your Heading styles. In dedicated formatting software, the tool generates it for you. In Reedsy, it is built automatically as you add chapters.

Inconsistent Paragraph Styles

Mixed formatting across a manuscript — some paragraphs using the Normal style, others using Body Text, others formatted directly — produces unpredictable output after KDP conversion. Before exporting, run a style audit on your document. In Word, open the Styles pane, select each paragraph in turn, and confirm it is using the correct named style. Any paragraph showing direct formatting overrides needs to be cleared and reset to the base style.

Images in CMYK Colour Mode

CMYK is the colour mode used for print. Kindle devices display in RGB. A CMYK image embedded in your ebook will display incorrectly — colours appear washed out or shifted — on every Kindle device and app. Convert all images to RGB in an image editor before embedding them. This applies to cover images as well as interior images, though KDP handles the cover separately from the manuscript file.

Fixed-Width Layouts

Ebook text must reflow dynamically based on the reader’s font size, device, and screen orientation. Fixed-width tables, text boxes, or columns that work in a print PDF will break on Kindle. If your manuscript contains any of the following, convert them to single-column flowing content before formatting for ebook:

• Multi-column layouts
• Text boxes or sidebars
• Tables wider than the screen width
• Fixed-position images or callout boxes

Print and ebook formatting are separate outputs requiring separate structural decisions. A file that looks perfect as a print PDF will almost always need adjustments before it is ready for KDP ebook submission.

The table below summarises each formatting mistake covered in this section alongside the specific fix to apply before uploading to KDP.

Formatting Mistake	Fix
No linked table of contents	Generate automatically from Heading styles in Word or use dedicated formatting software
Inconsistent paragraph styles	Run a style audit in Word; clear all direct formatting and reset to named styles
Images in CMYK colour mode	Convert all images to RGB in an image editor before embedding
Fixed-width layouts	Convert multi-column layouts, text boxes, and wide tables to single-column flowing content
Manual indentation using Tab or spacebar	Set first-line indent at the paragraph style level, not applied manually
MOBI file upload	Upload EPUB or DOCX only — MOBI was deprecated by Amazon in 2022

Formatting an ebook for KDP follows a consistent set of technical rules that apply to every title you publish, regardless of genre or length. Use the correct file type, apply paragraph styles through named styles rather than manual formatting, build a proper linked table of contents, and verify the output in KDP’s built-in previewer before you publish. The tools available — from free options like Reedsy Book Editor and Kindle Create to dedicated software like Atticus — handle most of the technical complexity once you understand what KDP’s conversion engine actually requires. Authors who learn this process correctly on their first book carry that knowledge across every subsequent title in their catalog, and that is where the real efficiency gain compounds.

Frequently Asked Questions

These are the questions authors ask most often before formatting their first ebook for KDP.