What is an .EPUB file and how do I open and view one?

What is an .EPUB file?

EPUB files are the most popular file format extension used for the storage of eBooks and other related content. The .EPUB format can store words, images, fonts, stylesheets, metadata and content tables. EPUBs are layout agnostic, which means the formatting isn’t affected by the size of the screen. In fact, you can view .EPUB files on screens as small as 3.5 inches.

What does .EPUB stand for?

The .EPUB format is simply short for ‘electronic publication’, making it one of the easier filename abbreviations to understand.

EPUB is the perfect way to describe files intended as the digital alternative to printed media, such as books and magazines.

History of the .EPUB file.

The International Digital Publishing Forum (IDPF) developed the .EPUB format and released it for use in 2007. It soon superseded the older Open eBook (OEB) standard, which had been launched in 1999.

.EPUB 2.0.1 was approved in 2010, with the .EPUB 3.0 specification arriving in 2011. It was superseded in 2014 by 3.1 and the current version, 3.2, came out in 2019.

The release of the .EPUB format coincided with the rise in popularity of eBooks and eReaders. The most popular eReader, Amazon’s Kindle, was - however - unable to display these files until 2022, when the Send to Kindle service was introduced.

What are .EPUB files used for?

Reading eBooks.

.EPUB files are primarily used in the viewing of eBooks. You can download and open them on eReaders such as Adobe Digital Editions (ADE), as well as smartphones, tablets or computers. The latest version, .EPUB 3.2, supports HTML, CSS and SVG, with built-in support for video, audio and even interactive features. However, people still use it primarily as a platform to read eBooks they’ve bought and downloaded, through online shops such as Apple Books and Google Play Books.

Creating eBooks.

You can create eBooks with a wide range of software. Adobe InDesign, Calibre on Windows and Apple’s Pages are just some of the programmes you can use to export to .EPUB format. Or, if you are comfortable with creating websites, you may be able to hand-code an .EPUB from scratch. You can do so with Calibre or webpage editing software such as Adobe Dreamweaver.

Official documents.

Many organisations use .EPUB to publish legal, judicial and parliamentary papers, research studies and other types of official documentation.

Discover more document file types and eBook file types.

Pros and cons of .EPUB files.

Like any technology, there are pros and cons to consider with the .XLS file format.

Pros.

• It works across multiple reader platforms.
  The use of XML and XHTML in .EPUB files helps to make them accessible and compatible with most devices. Due to their widespread usage, they are also popular with authors, publishers and retailers. Even Amazon, which used to rely solely on .MOBI files for its popular Kindle eReader, now allows .EPUB files to be converted for viewing.
• .EPUB files are designed to be resized.
  Unlike some similar file types, .EPUB files are ‘reflowable’. This means their content rearranges and realigns automatically to the screen size of your reading device. This avoids the need to zoom, pan and pinch in order to read.
• Digital rights management (DRM).
  Although the .EPUB format is open source, there is an optional layer that can contain DRM. This means you can make .EPUB files more secure than some electronic publishing files, to prevent them being copied, printed or shared.

Cons.

• Requires programming knowledge to build.
  You can create .EPUB files from scratch if you have knowledge of coding. However, if you don’t have any understanding of the syntax of XML and XHTML, you may struggle.
• Kindle compatibility.
  Although Amazon’s Kindle eReader is now compatible with the .EPUB format, you’ll need to use the Send to Kindle tool first.
• Digital rights management (DRM).
  Although the ability to use DRM on .EPUB files is generally a positive, it could create problems too. For example, if you buy an eBook via the Kindle store, it can only be read on a Kindle or the Kindle app. If you wanted to read it elsewhere, you would need to find a DRM removal tool online.

How to open an .EPUB file.

You can open and read .EPUB files on both Windows and Mac devices if you download Adobe Digital Editions to your computer.

1. Open Adobe Digital Editions on your machine.
2. Select ‘File’, then ‘Add to Library’.
3. Find the saved .EPUB file on your device. Double-click the .EPUB file you want to read.

How to create and edit an .EPUB file.

You can create and edit a document with Adobe InDesign. To turn a manuscript into an .EPUB:

1. Create a document in InDesign.
2. Place text, images and video into the document.
3. Preview fonts and polish your document’s page layout.
4. Use the ‘Publish Online’ to send your eBook to readers for reviewing and editing.
5. When you’ve finished editing, export the document as an .EPUB file.

To export to the .EPUB format:

1. With the document open, choose ‘File’, then ‘Export’.
2. Open a book and in the ‘Book panel’ menu, select ‘Export Book to EPUB’.
3. Specify your filename and location.
4. In the ‘Save as Type’ list, select ‘EPUB (Fixed Layout)’ or ‘EPUB Reflowable’, then choose ‘Save’.
5. In the ‘EPUB Export Options’ box, select your desired options and select ‘OK’.

How to open an .EPUB file as a PDF.

If you want to convert an .EPUB file into a PDF, you may want to use an EPUB to PDF converter. Usually it’s very straightforward:

• Upload the PDF you want to convert.
• Convert and then download the PDF version.

You can also convert other file types to PDF online using Adobe Acrobat online services.

Learn more about similar file types to .EPUB.

.MOBI

A file format used for storing eBooks, MOBI was primarily compatible with Amazon’s Kindle eReader and app. Current Kindle formats such as AZW3 are based on MOBI.

.PDF

Also known as Portable Document Format, PDF is an open standard. You can use it to make and edit documents containing links, form fields, audio and video. You can also sign PDFs electronically, making them useful as official documents.

.DOCX

One of the most popular document files in existence, DOCX files are created via Microsoft Word, but you can export them into other word processing programmes too. DOCX is widely used in home, academic and business environments.

.PAGES

The PAGES file format is Apple’s proprietary word processing answer to DOCX. PAGES isn’t cross-platform like DOCX, however, so can only be used on Apple devices.