When you finish writing your manuscript, one of the first decisions you face is format: EPUB or PDF?
Both are widely used for digital distribution, but they serve very different purposes. Understanding the difference helps you choose the right format — or know when to produce both.
What Is EPUB?
EPUB (Electronic Publication) is an open standard format maintained by the W3C. It is the native format for most modern ebook readers and apps:
- Apple Books
- Google Play Books
- Kobo
- Adobe Digital Editions
- Moon+ Reader (Android)
An EPUB file is essentially a ZIP archive containing HTML, CSS, and image files — structured like a mini-website. This means the text reflows to fit any screen size.
What Is PDF?
PDF (Portable Document Format) was designed by Adobe to preserve exact visual layout across any device or printer. A PDF always looks the same — fonts, margins, and page breaks are fixed.
PDFs are ideal when layout fidelity matters more than reading comfort.
Key Differences
1. Reflowability
| Feature |
EPUB |
PDF |
| Adjustable font size |
Yes |
No |
| Adjustable line spacing |
Yes |
No |
| Portrait/landscape reflow |
Yes |
No |
| Fixed page layout |
No |
Yes |
EPUBs adapt to the reader's preferences. PDFs do not. On a 6-inch e-reader, a PDF formatted for A4 paper will either be tiny or require horizontal scrolling.
2. Device Compatibility
EPUB works natively on:
- E-ink readers (Kobo, Kindle via Send-to-Kindle conversion)
- iOS and Android reading apps
- Desktop apps like Calibre and Adobe Digital Editions
PDF works on:
- Any device with a PDF viewer
- But often poorly on small e-ink screens
Note: Amazon Kindle does not natively support EPUB. You must either convert it to MOBI/KFX or use Amazon's Send-to-Kindle service, which auto-converts EPUB.
3. Accessibility
EPUB 3 has strong built-in accessibility features:
- Semantic HTML structure for screen readers
- Proper heading hierarchy
- Image alt text support
- ARIA landmarks
PDFs have more limited accessibility unless specifically created with accessibility tagging.
4. Editability
EPUBs are easier to update post-publication — you can open the ZIP, edit the HTML/CSS, and repackage. PDFs require the original authoring software to edit cleanly.
5. DRM and Distribution
Both formats support DRM (Digital Rights Management), but EPUB is the standard for most ebook retailers. Amazon uses its own proprietary format (KFX), but all major non-Amazon retailers — Apple, Kobo, Google — use EPUB.
When to Use EPUB
Choose EPUB when:
- You are distributing through ebook retailers (Apple Books, Kobo, Google Play)
- Your book is primarily text-based (novels, non-fiction, essays)
- Reader experience and accessibility matter
- You want reflowable text for different screen sizes
When to Use PDF
Choose PDF when:
- Layout is critical (cookbooks, art books, textbooks with complex figures)
- You are distributing to print-on-demand services
- Your audience will read primarily on desktop or large tablets
- You need to preserve exact typography and design
Should You Produce Both?
For most authors, yes. A common workflow is:
- Write in DOCX or Markdown
- Convert to EPUB for ebook distribution
- Convert to PDF for print-on-demand or author website downloads
EPUBMaker handles step 2 — converting your DOCX or TXT file to a clean, standards-compliant EPUB in seconds.
Summary
|
EPUB |
PDF |
| Best for |
Ebook readers |
Fixed layout, print |
| Reflowable |
Yes |
No |
| Kindle native |
No (convert) |
No (convert) |
| Accessibility |
Excellent |
Limited |
| File size |
Small |
Larger |
For most digital books intended for reading apps and e-readers, EPUB is the right choice. It is the format the industry has standardized on — flexible, accessible, and widely supported.