eBook Formats Explained: EPUB, PDF or Word — Which Do You Need?
What EPUB, print-ready PDF and Word files are for, which one each store expects, and how to prepare a manuscript so conversion goes smoothly.
The short answer
- EPUB is the file eBook stores and reading apps use. It *reflows*: the reader chooses the text size, so there are no fixed pages.
- A print-ready PDF is for paperbacks and hardbacks. Every page is fixed at your trim size (for example 6 × 9 in), with fonts embedded and margins that suit the page count.
- Word (.docx) is your editable master copy. Most platforms accept it as an upload and convert it themselves, but you get more control by preparing the EPUB and PDF yourself.
Most self-published authors need an EPUB for the eBook, a PDF interior for the paperback, and the Word file to keep editing.
EPUB: the eBook standard
EPUB is a package of web pages, a stylesheet, images and a navigation file. Because it reflows, design choices that rely on fixed positions (manual line breaks, tabs for indents, empty lines for spacing) can look wrong on a phone or e-reader.
A good EPUB has:
- A real table of contents built from your chapter headings, so readers can jump between chapters from the reader's own menu.
- Metadata: title, author, language and an identifier.
- Consistent styles for chapter titles, sub-headings, first paragraphs, quotes and scene breaks.
- A cover image (stores usually take the cover separately as well).
Amazon KDP, Apple Books, Google Play Books and Kobo all accept EPUB uploads.
Print-ready PDF: for paperbacks
A paperback interior PDF fixes every page. Things to get right:
- Trim size matches what you choose on the platform (6 × 9 in is common for non-fiction and many novels; 5 × 8 in or 5.5 × 8.5 in for shorter fiction).
- Margins: on KDP the inside (gutter) margin depends on the page count — at least 0.375 in for 24–150 pages, rising to 0.875 in for 701–828 pages — and outside margins must be at least 0.25 in without bleed.
- Fonts are embedded, so the printer uses exactly the font you designed with.
- Chapters start on new pages, with page numbers in the footer and a contents page that matches them.
Word: the master copy
Keep your manuscript in Word or Google Docs and use Heading 1 for chapter titles. Converters rely on heading styles to find chapters and build the contents, so a chapter title that's just bold text in a bigger size is easy to miss.
Preparing your manuscript for conversion
- Use Heading 1 for chapter titles and Heading 2 for sections.
- Indent paragraphs with the paragraph style, not tabs or spaces.
- Use a centred "* * *" line for scene breaks instead of empty lines.
- Keep images high quality (at least 300 DPI for print) and make sure you have the rights to use them.
- Remove tracked changes and comments before converting.
Try it free
Our eBook Creator turns pasted text or a Word file into a PDF, EPUB and Word file you can preview page by page — without changing your words. If your book has images, tables, footnotes or a complex layout, our formatting and conversion service prepares and proofs the files for you.
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