EPUB File Extension

What is EPUB file?

Files with the EPUB extension contain electronic publications - Electronic PUBlication, compressed with ZIP compression method, stored in an open format based on XML. Within the file, there is also some metadata on a given publication. It also enables to search through the text for specifics.

Such format may include:

• Content of a book, providing possibility to change the font size, and the option to display it with no division into pages.
• Raster or vector graphic.
• Copyrights - DRM,
• CSS stylesheets.

History of EPUB format

EPUB files have substituted the previous Open eBook format, introduced by the International Digital Publishing Forum – IDPF, in the year 2007. Currently, along with the MOBI and PDF formats, EPUB is the most popular format used for distributing electronic books or other publications for reading devices, although they can be opened also on mobile devices and computers equipped with proper software. In the EPUB 3.1 version, also audio and video data can be stored and it supports interactivity.

Programs which support EPUB file extension

Below you will find an index of software programs that can be used to open EPUB files divided into 7 categories according to system platform supported. Files with EPUB suffix can be copied to any mobile device or system platform, but it may not be possible to open them properly on target system.

Updated: 02/09/2024

How to open file with EPUB extension?

Problems with accessing EPUB may be due to various reasons. Fortunately, most common problems with EPUB files can be solved without in-depth IT knowledge, and most importantly, in a matter of minutes. The following is a list of guidelines that will help you identify and solve file-related problems.

Step 1. Install Sony Reader software

The main and most frequent cause precluding users form opening EPUB files is that no program that can handle EPUB files is installed on user’s system. The most obvious solution is to download and install Sony Reader or one to the listed programs: Calibre, OverDrive Media Console Phone, Stanzetta. Above you will find a complete listing of programs that support EPUB files, classified according to system platforms for which they are available. If you want to download Sony Reader installer in the most secured manner, we suggest you visit website and download from their official repositories.

Step 2. Update Sony Reader to the latest version

You still cannot access EPUB files although Sony Reader is installed on your system? Make sure that the software is up to date. Sometimes software developers introduce new formats in place of that already supports along with newer versions of their applications. The reason that Sony Reader cannot handle files with EPUB may be that the software is outdated. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using Sony Reader.

Step 3. Assign Sony Reader to EPUB files

If you have the latest version of Sony Reader installed and the problem persists, select it as the default program to be used to manage EPUB on your device. The method is quite simple and varies little across operating systems.

Change the default application in Windows

• Choose the Open with entry from the file menu accessed by right-mouse clicking on the EPUB file
• Next, select the Choose another app option and then using More apps open the list of available applications
• To finalize the process, select Look for another app on this PC entry and using the file explorer select the Sony Reader installation folder. Confirm by checking Always use this app to open EPUB files box and clicking OK button.

Change the default application in Mac OS

• By clicking right mouse button on the selected EPUB file open the file menu and choose Information
• Proceed to the Open with section. If its closed, click the title to access available options
• Select the appropriate software and save your settings by clicking Change all
• A message window should appear informing that This change will be applied to all files with EPUB extension. By clicking Continue you confirm your selection.

Step 4. Check the EPUB for errors

You closely followed the steps listed in points 1-3, but the problem is still present? You should check whether the file is a proper EPUB file. Being unable to access the file can be related to various issues.

1. Verify that the EPUB in question is not infected with a computer virus

If the file is infected, the malware that resides in the EPUB file hinders attempts to open it. It is advised to scan the system for viruses and malware as soon as possible or use an online antivirus scanner. If the EPUB file is indeed infected follow the instructions below.

2. Verify that the EPUB file’s structure is intact

Did you receive the EPUB file in question from a different person? Ask him/her to send it one more time. The file might have been copied erroneously and the data lost integrity, which precludes from accessing the file. If the EPUB file has been downloaded from the internet only partially, try to redownload it.

3. Verify whether your account has administrative rights

Some files require elevated access rights to open them. Switch to an account that has required privileges and try opening the Open EBook Format file again.

4. Check whether your system can handle Sony Reader

If the system is under havy load, it may not be able to handle the program that you use to open files with EPUB extension. In this case close the other applications.

5. Ensure that you have the latest drivers and system updates and patches installed

Regularly updated system, drivers, and programs keep your computer secure. This may also prevent problems with Open EBook Format files. It is possible that one of the available system or driver updates may solve the problems with EPUB files affecting older versions of given software.

Do you want to help?

If you have additional information about the EPUB file, we will be grateful if you share it with our users. To do this, use the form here and send us your information on EPUB file.