What Is an EPUB File (and How Do I Open One)?

How-To Geek

By Brady Gavin

Updated Oct 15, 2023

Here's how to crack that virtual book open.

Joe Robinson / How-To Geek

EPUB files are popular for storing eBooks and other content because they can display on screens as small as 3.5" and are supported by many eReaders.
To open an EPUB file, use Calibre or another free program on your desktop, or use the preloaded iBooks or Google Play apps on your iPhone or Android device.
If you want to convert an EPUB file, use Calibre or one of the free online file conversion sites like DocsPal, Convertio, ConvertFiles, or Zamzar.