.EPUB File Extension
Standard open e-book format with reflowable typography and XHTML layout structure.
application/epub+zip
50 4B 03 04 ... 6D 69 6D 65 74 79 70 65 61 70 70 6C 69 63 61 74 69 6F 6E 2F 65 70 75 62 2B 7A 69 70
Format Architecture & Technical Specifications
EPUB is an HTML-based open e-book format defined by the International Digital Publishing Forum (IDPF). It supports reflowable text layout, vector graphics, table of contents metadata, and CSS styling.
How to Open .EPUB Files
1 Apple Books
Double-click EPUB file on Mac or iPhone to open in Apple Books.
2 Calibre Reader
Use Calibre e-book manager to read, edit, and sync EPUB files across devices.
Compatible Software Programs
Calibre E-Book Management
windows, mac, linux • Free
Apple Books
mac, ios • Free
Readium Web Reader
windows, mac, linux • Free
Security Considerations & Verification
HTML e-book container. Safe.
- Validate mimetype file inside EPUB Zip package is uncompressed and at offset 30.
Frequently Asked Questions
What is a .EPUB file?
A .EPUB file is a Electronic Publication E-Book associated with Documents. Standard open e-book format with reflowable typography and XHTML layout structure.
How do I open a .EPUB file on Windows or Mac?
You can open .EPUB files using Calibre E-Book Management, Apple Books, Readium Web Reader. If you do not have native software installed, you can use AnyFileX's free File Identifier or convert .EPUB to a standard format in your browser.
Is a .EPUB file safe to open?
This format carries a safety rating of Low Risk. HTML e-book container. Safe.
Can I convert a .EPUB file to other formats?
Yes! .EPUB can be converted to formats such as .PDF, .MOBI directly in your web browser.
What should I do if a .EPUB file is corrupted or won't open?
If your .EPUB file displays an invalid header or signature error, check its magic bytes hex header (50 4B 03 04 ... 6D 69 6D 65 74 79 70 65 61 70 70 6C 69 63 61 74 69 6F 6E 2F 65 70 75 62 2B 7A 69 70) using AnyFileX's Magic Byte Detector or follow our step-by-step file repair guide.