eBook Formats: EPUB, MOBI & PDF Compared
Reflowable digital book layouts vs. fixed-page documents for e-readers and mobile devices.
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Format Comparison & Technical Specifications
| Output Format | MIME Type | Specification | Type |
|---|---|---|---|
| EPUB EPUB | application/epub+zip | W3C-EPUB-33 | Electronic Publication Format |
| PDF eBook | application/pdf | ISO-32000-2 | Document eBook |
| MOBI pocket eBook | application/x-mobipocket-ebook | MOBIPOCKET-SPEC | Mobipocket Kindle eBook |
| AZW3 Kindle Format 8 | application/vnd.amazon.ebook | AMAZON-KF8-SPEC | Amazon KF8 eBook |
| FB2 FictionBook 2.0 | application/x-fb2+xml | FICTIONBOOK-SPEC | FictionBook XML Document |
Technical Specifications & Codec Breakdown
EPUB vs. PDF on e-Readers
Reading a PDF on a 6-inch e-reader screen is frustrating because you have to pinch, zoom, and pan across rigid page coordinates. EPUB is reflowable HTML: enlarge the text, and words re-wrap naturally to fit any screen size or font preference.
The Open EPUB Standard vs. Amazon Kindle
EPUB is the open international standard used by Apple Books, Kobo, and Android e-readers. Amazon historically used proprietary MOBI and AZW formats, but modern Kindles now officially accept EPUB files directly.
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