Quick Verdict
Use EPUB when…
Use EPUB for distributing books and long-form reading content on e-readers (Kobo, Apple Books). EPUB is the universal e-book format optimised for reading offline.
Use HTML when…
Use HTML for web publishing — browser-based reading, online documentation, and anything that should be indexed by search engines and accessible via URL.
EPUB vs HTML: Feature Comparison
| Feature | EPUB | HTML |
|---|---|---|
| File structure | ZIP archive of HTML + CSS + XML | HTML file(s) with CSS |
| Offline reading | Excellent (single packaged file) | Possible but cumbersome |
| E-reader support | Kobo, Apple Books, most readers | Not supported on e-readers |
| Reflowable text | Yes (core EPUB feature) | Yes (responsive HTML) |
| Web browsing | No (requires e-reader app) | Yes (native browser format) |
| Search indexing | Limited (not indexed by Google directly) | Full (Google indexes all HTML) |
| DRM support | Adobe DRM, Apple FairPlay | No standard DRM |
| Kindle support | Indirect (Send to Kindle or convert) | No |
When EPUB wins
- ✓File structure: ZIP archive of HTML + CSS + XML
- ✓Offline reading: Excellent (single packaged file)
- ✓E-reader support: Kobo, Apple Books, most readers
When HTML wins
- ✓File structure: HTML file(s) with CSS
- ✓Offline reading: Possible but cumbersome
- ✓E-reader support: Not supported on e-readers
Frequently asked questions
Can I read EPUB files in a browser?
Not natively — browsers don't open EPUB files. You need an EPUB reader extension (EPUBReader for Firefox, Epub Reader for Chrome) or an app like Apple Books, Kobo, or Calibre's viewer. For web-based reading, convert EPUB to HTML first.
How do I convert EPUB to HTML?
Calibre: right-click the book → Convert books → set output to HTML. Pandoc: `pandoc input.epub -o output.html --standalone`. The converted HTML contains all the book's content in a single file or a folder of linked HTML files.
How do I convert HTML to EPUB?
Pandoc: `pandoc input.html -o output.epub`. Calibre: add the HTML file as a book, then convert to EPUB. Sigil (free EPUB editor) is excellent for fine-tuning the EPUB structure. For a full website, Wget the HTML first then convert with Calibre.
More comparisons
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