What is an EPUB file?

EPUB (.epub) is the open standard format for digital e-books, maintained by the W3C. It is a ZIP archive containing XHTML content, CSS stylesheets, images, navigation data and metadata. EPUB is supported by Apple Books, Google Play Books, Kobo, Adobe Digital Editions and most e-reading applications.

Are my EPUB files uploaded?

No. Books you open from your device stay on your device and are rendered locally. Only the public sample book is requested from the server.

Can I adjust the font and layout?

The viewer provides basic reading functionality including chapter navigation and content rendering. Font and layout adjustments depend on the EPUB's embedded CSS and the viewer's capabilities.

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EPUB Viewer

Free online EPUB viewer. Open and preview e-books (.epub) directly in your browser — no upload, no software.

.epub

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About this file format

EPUB (.epub, electronic publication), standardized by the International Digital Publishing Forum (IDPF, now part of W3C) in 2007 (EPUB 2) and 2011 (EPUB 3), is the open standard for digital e-books. An .epub file is a ZIP archive containing XHTML content files, CSS stylesheets, images, a navigation document (NCX for EPUB 2, nav for EPUB 3) and a package document (content.opf) with metadata. EPUB supports reflowable text, fixed layouts, embedded fonts, SVG images, audio, video and JavaScript interactivity.

EPUB Viewer

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