What is an EPUB file, and How to Open, Convert, Create it?

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You would be using EPUB format as an ebook file format but don’t know what it means and how to open it.

The EPUB, short for Electronic Publication, is a file extension used for ebook format and is highly popular among publishers and consumers.

It is a standard digital publication format supported by most e-reader devices and software programs. Also, it was named by the International Digital Publishing Forum (IDPF) in September 2007.

What is an EPUB file?

An EPUB file is a standard ebook file format that can store content like words, images, fonts, stylesheets, metadata, and tables.

It is supported by electronic devices like smartphones, ebook readers, tablets, and computers.

Moreover, the formatting of the epub file is known as layout agnostic, which means the formatting doesn’t change with screen size. The epub file is expected to display content in screen size as small as 3.5′.

Additionally, EPUB’s latest version, EPUB 3.2, can support HTML, CSS, SVG, and embed interactive audio and video.

As mentioned earlier that it is maintained by IDPF and is based on three open standards.

  • Open Publication Structure (OPS), which defines file content markup.
  • Open Packaging Format (OPF), which defines file ebook structure.
  • Open Container Format (OCF) compresses the file content in a compressed format.

How to open the EPUB file?

The EPUB file can be opened on multiple devices using various software formats.

The ebook readers that support epub files are:

  • Kobo Reader
  • B&N Nook
  • Apple’s Books

However, Amazon Kindle does not support epub files. You have to first convert the file into MOBI and PDF format.

The epub file can be opened in Windows, Mac, Linux, Android, and iOS by following software programs.

Browser extensions for Firefox and Chrome are

The other way to epub file is to upload it in Google Playbooks and open it.

Interestingly, the EPUB file format is structured like a ZIP file. So, if you would like to have the content that a particular file is using, you need to rename the file extension from EPUB to ZIP.

Now, you can use any compression tool like 7-zip to know the inside content like images, HTML, and styles files.

How to convert an EPUB file?

The EPUB file can be converted into multiple file formats such as PDF, TXT, FB2, HTML, MOBI, and many files.

The famous app and software programs that help in converting EPUB files are

  • Calibre – It will convert EPUB files into HTML, TXT, PDF, LIT, LRF, MOBI, FB2, PDB, RTF, and SNB.
  • Zamzar will convert EPUB file format into TXT, PDF, FB2, and similar text formats.
  • Online ebook Converter will convert EPUB files into document file formats like AZW and PDF.

If you are Windows 10 user, then you can open the EPUB file using Microsoft Edge. For this, you have to right-click on the file and select open with “Microsoft Edge.

Also, the Adobe Acrobat Reader can be used to open the EPUB file. For this, Adobe has a separate software program known as Adobe Digital Editions to open PDF and EPUB files on your PC or MAC.

Moreover, you can also convert EPUB file format into other formats by opening the file using the most popular software or apps and exporting it using the available file format.

How to create an EPUB file?

The EPUB file can be created using Adobe InDesign digital editions. If you are familiar with designing for print, designing an EPUB file would be easy.

When you have created content using Adobe InDesign, you need to export it as an EPUB file.


The EPUB file is supported and opened by most software programs and apps, but it is sometimes confused by other extensions.

The other very similar extension to EPUB is PUB, EPM, and EBM file extension. These file formats that are similar to EPUB are not identical in properties.