What Is an EPUB File?

How to Open, Edit, and Convert EPUB Files

EPUB Files
EPUB Files.

A file with the EPUB file extension, short for electronic publication, is a popular and freely available eBook standard, supporting more hardware eBook readers than any other similar file format.

EPUB 3.1 is the latest EPUB version and supports embedded interactivity, audio, and video.

EPUB is sometimes stylized as ePub.

How to Open an EPUB File

EPUB files can be opened in most eBook readers, like the B&N Nook and Kobo eReader.

EPUB files have to be converted before they're usable on the Amazon Kindle (see How to Convert an EPUB File below).

EPUB files can also be opened on a computer with a number of free programs, like Calibre, Adobe Digital Editions, EPUB File Reader, Stanza Desktop, Okular, Sumatra PDF, and many more.

Plenty of iPhone and Android apps also exist that allow viewing of EPUB files. There's even a Firefox Add-on (EPUBReader) and Chrome app (Simple EPUB Reader) that allow you to read EPUB files in the browser just like other documents.

Google Play Books is another place you can open EPUB files. This works by uploading the EPUB file to your Google account and viewing it through their web client.

Since EPUB files are structured just like ZIP files, you can actually rename an EPUB eBook, replacing the .epub with .zip, and then open the file with your favorite file compression program, like the free 7-Zip tool.

Inside you should find the contents of the EPUB eBook in HTML format, as well as the images and styles used to create the EPUB file.

Note: Some EPUB files are DRM-protected, which means they can only open on certain devices that have been authorized to view the book. If you can't open the eBook using some of the programs above, you might look into whether or not the book is protected in that way so you can better understand how to open it.

How to Convert an EPUB File

Since most computers don't really have "default" program for opening EPUB files, unless one has been purposefully installed before, they also usually don't have one that converts EPUB files.

The first thing you should if you want to convert an EPUB file to another format is to use the free Calibre program. It converts to and from most other eBook formats, including ones compatible with the Amazon Kindle. Some of the supported conversions include EPUB to FB2, HTML, LIT, LRF, MOBI, PDF, PDB, RTF, TXT, and SNB.

Online eBook Converter is another way to quickly create an EPUB file from another format like AZW, TCR, and others, through an online conversion service. They also have ePub Converter so you can convert other file types, such as PDF, to the EPUB format. This is a great, super-simple way to create an eBook from your original document file.

Another online EPUB converter I'll mention is Zamzar. You can use that website to convert the EPUB file to PDF, TXT, FB2, and other similar text formats.

Though probably not as effective as using Calibre or the online converters, you could try to convert an EPUB file by opening it in one of the other eBook readers from above and choosing to save or export the open file as another file format.

If none of those methods work out, check out our Free File Conversion Software Program or Online Service list, which is full of other tools that might come in handy.

More Information on EPUB Files

EPUB is the successor of the Open eBook Publication Structure, and became an official IDPF specification in 2007. You can read more about this on the IDPF's EPUB page.

The EPUB file format supports embedding files like GIF, PNG, JPG, and SVG images.

More Help With EPUB Files

See Get More Help for information about contacting me on social networks or via email, posting on tech support forums, and more. Let me know what kinds of problems you're having with opening or using the EPUB file and I'll see what I can do to help.

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