How to Open an EPUB File (and What It Is)

If you read a lot of e-books or are into self-publishing, you will be familiar with the concept of EPUB files. But if you are unfamiliar with them and wondering how to open and use them, this guide is for you. Here’s how to open an EPUB file and what it is exactly.

Read more: 15 Best E-Book Reading Apps for Android


An EPUB file, compared to the closed proprietary nature of other eBook file formats, is an open source eBook format supported by most eBook readers (Kindle being the main exception). Short for electronic publication, EPUB files can be read by compatible readers and software on desktop browsers, smartphones, and tablets.


What is an EPUB file?

standard ebooks

An EPUB file – short for electronic publication – is an open source e-book file format recognized by most e-book readers. The biggest exception to this is Amazon’s Kindle, which has its own closed, proprietary e-book file format called MOBI. However, in 2022 they started moving away from MOBI and towards their own version of EPUB. So, in the future, it is entirely possible that all EPUB files will eventually be compatible with Kindle.

caliber app

But most other major e-book readers, as well as specific third-party software and browsers, can also open EPUB files. This can range from the Apple Books app to the Kobo eReader to something as basic (and ugly) as the free cross-platform Caliber software app. You most often see EPUB files on sites that produce legal copies of public domain books, such as Project Gutenberg and Standard E-Books.

How to open an EPUB file

It’s easy to open an EPUB file, no matter what operating system you’re using. Let’s review each.

Windows 11

epub windows

In Windows 11, you have a few options. You can use the browser, an app from the Microsoft Store, or a third-party app like Calibre. The easiest way is to use the Edge or Chrome browser. Both run the same plugins, so you can use EPUBReader for free. Once installed, right-click the EPUB file on your computer, click Open with and choose the browser with the plugin installed. The EPUB file will then open.

microsoft store epub

If a browser plugin doesn’t appeal, there are options in the Microsoft Store, some free, some paid. However, the user interface of each leaves a lot to be desired. A third option is the Caliber app. Just install it and use it to open EPUB file. But again, Caliber looks very dated and very ugly. The browser option is the most visually appealing way to go here.

Macs, iPhones and iPads

apple books app

On an Apple device, whether it’s a Mac or iOS, by far the easiest solution is to use the built-in Books app. Books purchased through the Apple Store are automatically EPUB files and will open immediately in Books. If you download an EPUB book to your device, for example from Gutenberg, you just need to double click on it. It will then open in the Books app.

You can also right-click on the EPUB file and use the Open with option to see your opening options. At the moment I can only use the Books app, but if Caliber was installed, for example, it would also appear here. You can also select Show package contents if you wanted to dig into the different components.

right click epub file mac

On iOS, tap the EPUB download link. At the bottom of the screen you will now see a blue Download link. Press it.

download epub ios

Once the EPUB has been downloaded, you will now see a Open in link. Press it.

open epub in ios

The share menu will now appear. Scroll until you see Books and select it. The EPUB will now open on your device.

open epub in ios books

There are also a few third-party options in the App Store, as well as Calibre. But quite honestly, the Books app does the job and is already installed on your device. So why reinvent the wheel?


If you are using an Android device (and reading Android Authority, you better!), the best option for opening EPUB files is Google Play Books. In addition to e-books, you can also use the app for audiobooks and comics, so it’s a good all-purpose reading app.

How to convert an EPUB file

convert to caliber

If you look online at Google or your app store of choice, you’ll see that there are plenty of apps that claim to convert EPUB files to other formats (or other formats to EPUB). I’m sure they do a good job, but in terms of longevity, nothing beats Caliber, which has been around since 2006. It can read e-books, as well as convert and store them in some sort of organized system. The application is under constant development, but its appearance is permanently stuck in 2006.

When you load the book you want to convert, you can specify a wide range of file formats, as well as edit metadata, change cover, add a table of contents, and more.

Read more: How to self-publish a book on Amazon


No, the Kindle cannot open EPUB files. You will need to convert the EPUB file to MOBI, which is Amazon’s file format for Kindle.

It depends on the use case. An EPUB is easier to read on eReaders, and the text looks and flows better. However, if you are looking to print the pages, a PDF is much better.

Yes, but you will need to use a dedicated third-party app that will modify the code for you.

Any type of file can theoretically contain malware. Exercise caution at all times, and if in doubt, check the file with a malware scanner.

Yes, but to keep the file size reasonable, it’s best to use JPG images.

Not natively, but you can get Google Workspace plugins that will open the file in Docs. However, the formatting can be distorted.