EPUB vs MOBI vs PDF Which Format Is Right For You?

If you’re considering indie publishing, you’re probably wondering about the differences between EPUB vs MOBI vs PDF. Here’s your handy guide!

It is the age of e-readers. Today, people expect to consume whatever content they want on the go, whether that’s the latest episode of Empire or a breaking report from a company they follow. 

If you want to reach your readers where they are, you must ensure your content is available. That means formatting your self-published book correctly, and that in turn means understanding EPUB vs MOBI vs PDF.

Each file format provides different benefits and is suited to specific platforms, but you can’t publish your content effectively until you understand how it works. Considering more than 4 million books were published in 2019 in the United States alone, you’ve got to stand out against the competition. And that starts with the proper ebook formats.

Examining the Different Ebook File Types


Let us assume for the sake of argument that you are self-publishing. Typically, you can choose to publish on just one platform or many, and each publishing platform uses different ebook formats. If you decide to become exclusive to one platform – say, Amazon kindle – that will minimize the number of file formats needed.

However, it isn’t the best way to distribute your books as widely as possible. If you want your audience to have access to you regardless of their preferred reading app and device, you will likely need to use all three formats at some point.

So what are they? And how do they work?


EPUB logo
Learning the EPUB file format is more or less a necessity for publishing novels or non-fiction books

EPUB is widely supported. Almost every publishing platform uses it.

EPUB is a reflowable file format. That means depending on the size of the device and the app rendering it, the text and content will become larger or smaller as needed. This is much better than a fixed layout, which can look terrible on some devices.

As such, learning the EPUB file format is more or less a necessity for publishing novels or non-fiction books.


The MOBI format is used for Amazon publishing. More specifically, MOBI is the only file format used for Amazon. You upload your MOBI file through the Kindle Direct Publishing (KDP) dashboard; from there, your ebook is pushed to their marketplace.

There are a few ways to do this. One of the most effective and popular platforms is Calibre, which will turn a Word document into a MOBI file for you in seconds, though there is a learning curve.


Lastly, you can opt for PDF files (portable document format), but this is somewhat limited in use. Granted, PDF is the go-to file format for some situations. That includes if you want to distribute your content yourself, say a business whitepaper, or if you are publishing print books.

When to Use EPUB vs PDF vs MOBI

The answer to which file format is best depends on what you want to do with your books.

When to Use EPUB

Among the platforms that rely on EPUB are:

  • Apple iBooks for iPad and iPhone
  • Barnes and Noble Nook
  • Kobo
  • Android
  • Google Play 
  • Adobe Digital Editions

… and numerous other kinds of multimedia platforms.

For instance, if you intend to publish on Apple’s iBooks, you will have to use EPUB. The same is true for many of the above formats and many more worldwide.

ALL of the major self-publishing marketplaces do accept EPUB. This is because it has the widest application and use. However, there is one major exception to this rule.

When to Use MOBI

Amazon uses both MOBI and AZW3 file types. Until mid-2021, Amazon only accepted MOBI file uploads. However, they have since started accepting epub uploads. However, the final title will always be converted into a MOBI file format.

It is still best practice to work with MOBI directly when working in the Kindle Direct Publishing dashboard, as it gives you greater control over the final layout of your title. Uploading the EPUB will result in an automatic conversion which could alter your formatting. 

When to Use PDF Files

When uploading a print manuscript to various retailers, it typically needs to be PDF or Word. For example, Kindle requires PDF, whereas Barnes and Noble will allow either. Again, you’ll need to check with each platform for specific upload instructions.

You can also use PDF as an ebook file. If you’re selling your own books or whitepapers off your website, this may prove the easiest way to go. Ditto if you are posting free downloads on your website.


Typically, EPUB is better than PDF for screen reading. In addition to being reflowable, EPUB easily allows indexing and bookmarks, which substantially increases the reading experience. Therefore, when it comes to ebook publishing, EPUB is always better.

If you want to upload print files, however, PDF is better. This allows you to adjust fonts to the specifications of international digital publishing forum. This open standard practice is easily adoptable by a wide variety of software.


There is one instance in which MOBI might be better for you than EPUB. If you’re exclusive to Amazon, you cannot sell anywhere except on their platform. That’s a limiting factor, but it does allow you to participate in their KDP Select program.

KDP Select is a trade: You give Amazon exclusive rights to your book; they push it to their Kindle Unlimited program. Then you get paid for each page Kindle readers finish. It limits the competition, as no one who isn’t exclusive can compete within this aspect of the Kindle app.

While KPD uses MOBI, remember you can still upload as an EPUB file. And with the demise of Mobipocket, there may be no reason not to use EPUB alone.


No, PDF isn’t better than MOBI. It is the right call for print publishing, that’s all. If you are publishing a Kindle ebook or any other kind, it’s not a suitable ebook file format.  

Final Word on EPUB Vs MOBI Vs PDF

All file types offer some protections, such as digital rights management to reduce copyright infringement. 

The main differences to consider when choosing file formats are which sellers you will use and whether any of your platforms will not accept the EPUB format. As it is used everywhere, from Amazon to Barnes & Noble, there’s little reason to pressure yourself to do otherwise.

Before deciding on EPUB books as your exclusive digital file format, the only advice we’d give is to talk to the distributors and make sure that is the best option for you. Online research will also help here, so make sure you do your due diligence.


Which file format is best for smartphones?

Almost all smartphones can easily read the EPUB file format, whose latest version is EPUB3. That includes Androids, iPhones, Sony, etc. Most can also read the Kindle format and PDFs, though the latter may look fuzzy or render weirdly on smaller screens.

What is the difference between EPUB, MOBI and PDF format?

The main difference between these file formats is the software you use to format them and the devices on which you can read them. Various self-publishing platforms also accept different file types, though almost all will accept EPUB.

Do you need to know CSS or HTML to format files?

No. Multiple programs are available to turn Word files into the required file types for electronic publication.

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  • Bryan Collins is the owner of Become a Writer Today. He's an author from Ireland who helps writers build authority and earn a living from their creative work. He's also a former Forbes columnist and his work has appeared in publications like Lifehacker and Fast Company.