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File Format Guide

What is a .EPUB file?

The EPUB format (short for Electronic Publication) is an ebook format that can use either lossless or lossy compression depending on how it is saved. EPUB is an open, royalty-free standard.

.EPUB at a glance

CategoryDocument
TypeEbook
CompressionMixed
Open standardYes
Opens in web browsersNo
Typical file sizeSmall

How to open a .EPUB file

You can open EPUB files with Apple Books, Calibre, and most e-readers. If a program on your device cannot read one, the quickest fix is to convert it to a more common format — no software install required.

EPUB pros and cons

Strengths

  • reflowable text that adapts to any screen
  • the open e-book standard
  • supports chapters, images, and metadata

Limitations

  • not ideal for fixed-layout or print
  • not editable like a word document

What .EPUB files are used for

  • e-books for most e-readers
  • reflowable publications

Need to convert a .EPUB file?

Convert EPUB to and from other formats free in your browser — no signup to start, no watermarks.

Open the EPUB Converter