What you should know
EPUB is the open standard for digital books, maintained by the W3C. An EPUB is an archive containing HTML, stylesheets, images and the book's metadata; text reflows to the screen size and to the font chosen by the reader.
It is read by most e-readers, with the notable exception of Kindle devices, which use their own format — except through Amazon's document-sending feature, which accepts it.
Strengths
- Reflowable text: font size, line spacing, dark theme
- Open standard, royalty-free
- Navigation through table of contents and bookmarks
- In-text search and annotations supported
Limitations to know
- Rendering varies between e-readers and applications
- Complex layout hard to guarantee, unlike PDF
- No DRM by default, which deters some publishers
- Mathematical formulas and comics are problematic
When to use it
Publish in EPUB for a novel, an essay or a guide the reader will enjoy on an e-reader or tablet. For a fixed-layout document — technical manual, catalogue, comic — PDF remains safer.
Quality, size and compatibility
Convert from DOCX or structured HTML for a clean EPUB. From PDF the result is often mediocre: PDF does not contain the logical structure of the text, and the conversion yields chopped paragraphs and an inconsistent table of contents.
Frequently asked questions
- Can I read an EPUB on Kindle?
- Not directly: Amazon uses its own formats. You can still send the file through the document-sending feature, which converts it automatically.
- Why is an EPUB made from a PDF malformed?
- Because PDF describes positions, not structure: headings and paragraphs are not identified as such. Start from a DOCX or HTML for a clean result.