Understanding Ebook Formats: A Comprehensive Guide

| | September 13, 2023

In the modern digital era, reading books has evolved into a more portable and convenient way, with eBooks becoming more popular than ever.

As a result, publishers, authors, and readers must understand the different eBook formats available to ensure compatibility across various devices.

With the rise of eBooks and e-Readers, there are now various formats available for authors and publishers to choose from.

In this comprehensive guide, we'll cover the various ebook formats, their pros and cons, and how to choose the best format for your ebook.

We will also cover some of the best eBook creation tools that can help you create ebooks in the right format.

Let's get started.

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eBook Formats

eBook Formats Explained

As an avid reader, I've encountered various eBook formats that offer different features and benefits.

Let's delve into the world of eBook formats and understand what they are. 

An eBook format refers to the way an ebook is created and published, and there are many types available on the market. These formats range from familiar ones like PDF, ePUB, and MOBI to less popular ones like ODF and LIT.

Knowing the different eBook formats can help you choose the right one for your needs, whether it's for reading, creating, publishing or hosting an eBook

So, let's explore below the exciting world of eBook formats together!

What are the Top 5 eBook Formats?

When it comes to eBook formats, there are plenty to choose from, but some stand out as the most common.

In addition to the plain text file (TXT), there are three relatively popular formats: EPUB, MOBI, and AZW. PDF also deserves a mention as a widely-used format that is particularly useful for formatting documents. 

EPUB is widely accepted and is the recommended format for Amazon. MOBI and AZW are Amazon proprietary formats that are compatible with Kindle devices.

Choosing the right eBook format for your project depends on a range of factors, such as the intended audience, device compatibility, and the types of content you want to include.

By understanding the pros and cons of each format, it's easier to make an informed decision that will ensure maximum compatibility and reach for your eBook.

Let's learn more about these 5 popular eBook formats below.

Popular eBook Formats


EPUB stands for Electronic Publication, and it is an ebook format that allows for the creation of dynamic and interactive digital publications. EPUB files are designed to be readable on a variety of devices, including smartphones, tablets, and e-readers.

Unlike other eBook formats, EPUB supports reflowable text, making it easier to read on various devices and is available as an open standard. Thus, anyone can create and distribute EPUB files without having to pay royalties or licensing fees.

This has contributed to the popularity of EPUB as a publishing format. It is a highly versatile format that supports a range of features, including audio and video, interactive graphics, links, bookmarks, and embedded fonts. 

As I have mentioned above, EPUB files can be optimized for different screen sizes, making them ideal for reading on devices with different screen sizes. Thus EPUB formatted eBooks are compatible with most devices, including iOS, Android, and Windows.


MOBI, short for Mobipocket, is an eBook format created by Mobipocket SA, a French software company acquired by Amazon in 2005.

Amazon Kindle is one of the most popular eReader platforms in the world, and the MOBI format is optimized for use on these devices. This means that readers can easily download and read MOBI eBooks on their Kindle devices or apps without having to convert the files.

MOBI files are small in size compared to other eBook formats, which makes them ideal for use on mobile devices and on devices with limited storage space.

If your device doesn't support MOBI format, I recommend you to try online converter like Docspal or Zamzar which can convert MOBI files into formats like EPUB, LIT, LRF, PDB, PDF, FB2, RB, and more.

#3 PDF

I have always been fascinated by the popularity of the Portable Document Format or PDF, which is one of the oldest and most widely used eBook formats out there.

Produced by Adobe, this format offers a fixed layout for eBooks, making it perfect for printing and graphic-rich content and it is compatible with most devices, including iOS, Android, and Windows.

This is why PDFs have been used for everything from academic textbooks to manuals and user guides. However, PDFs are not ideal for reading on eReaders, and they require the user to zoom in and out to read the text.

Thus, unlike EPUB and MOBI, PDF is not reflowable, and the layout remains the same on all devices. It supports multimedia, hyperlinks, and annotations. 

If you are looking for a versatile eBook format that works on all devices, then EPUB might be the way to go.

Nonetheless, PDFs are still a valuable option when it comes to creating and publishing multimedia eBooks with detailed visuals and complex designs.

#4 AZW

AZW is Amazon's proprietary format, similar to MOBI, but with DRM (Digital Rights Management) protection.

AZW is only compatible with Kindle devices and Kindle apps.

If you're a Kindle user like me, you'll be familiar with the AZW format. Amazon's proprietary format, AZW started as a variant of MOBI but has since evolved into AZW3, also known as Kindle Format.

It's the default format for newer Kindle models and can support multimedia content like video and sound. However, because it's proprietary, it's not as widely supported on other e-readers as the more open EPUB format.

But as an Amazon loyalist, I find the AZW format to be reliable and convenient, especially for purchasing books directly from the Kindle Store.

Overall, the choice of eBook format comes down to personal preference and compatibility with your devices, but for Kindle users, AZW is a great option.


Ah, the plain old TXT file. It's the simplest of all eBook formats, with no fancy formatting applied except for space, paragraph breaks and line breaks.

It's basically just raw text put into a file. As a result, you don't get any of the multimedia features that come with other formats like EPUB, MOBI, AZW or PDF. 

However, it is a widely accepted format that is compatible with almost every eBook reader available. It's also one of the smallest file sizes of all the formats, which is great for those with limited storage space. 

Although the lack of formatting may not be ideal for some books, it's perfect for eBooks that just contain mostly text like classic literature, biographies or memoirs.

You may not get fancy images, videos or interactive content with a TXT file, but sometimes simplicity is the way to go.

The Two Kinds of eBook Formats

Now that we have explored the top five eBook formats - TXT, EPUB, MOBI, AZW, and PDF - let's dig deeper into the two main types of eBook formats.

The first type is platform-specific formats, such as Amazon's MOBI and AZW, and they can only be read on devices that support those formats.

On the other hand, the second type is platform-independent formats, such as EPUB, which can be read on a variety of devices such as smartphones, tablets, and e-readers.

As an author or publisher, it's important to choose the right eBook format based on your target audience, the type of book you are publishing, and the devices on which you want your readers to access your content.

So, take into consideration the advantages and disadvantages of each format before making a decision.

EPUB: The Widely Accepted eBook File Format

EPUB is the most widely accepted and functional e-book format. Compared to other formats, EPUB is more efficient and supports fixed-layout content, making it a great choice for books with lots of text and images.

It's also intended as a single format that publishers and conversion houses can use in-house, as well as for distribution to consumers.

For these reasons, EPUB is supported on almost all digital platforms and is a widely accepted eBook file format that every company recommends without any hesitation. 

From my own personal experience, EPUB files have always been easy to download and read on any device, making it a convenient option for anyone who enjoys reading on-the-go.

Which eBook Format is Right for You?

So, after looking at all the popular eBook formats in detail, it's time to decide which format is right for you.

Choosing the right ebook format depends on several factors, such as the type of content you're publishing and the devices you're targeting. Here are some tips to help you choose the right ebook format:

  • For novels, fiction, and non-fiction books, use EPUB as it's widely supported and offers reflowable text for better readability.
  • For textbooks, technical manuals, and other fixed-layout content, use PDF as it ensures consistent formatting across devices.
  • If you're publishing on Amazon's Kindle store, use MOBI or KF8, depending on the features you require and the devices you're targeting.

Morever, if you're an avid book reader and prefer Kindle for reading eBooks, then, I would recommend you to go for the MOBI format. MOBI is the preferred file format for Kindles.

However, if you're looking for a widely accepted file format that is supported on almost all digital platforms, then EPUB is the way to go. It offers reflowable format that easily adapts to small screens and other devices.

Ultimately, the decision solely depends on your personal preferences and the purpose of the eBook.

eBook Formatting Tips

When publishing an eBook, formatting is essential to ensure a seamless reading experience for your audience. Here are some formatting tips to keep in mind:

Images and Graphics

Images and graphics can enhance the reading experience, but too many images can increase the file size and slow down the loading time.

It's best to compress images and graphics using image compressor tool like tinypng before adding them to your eBook.

Fonts and Typography

Choosing the right font and typography can make a huge difference in the readability of your eBook.

Stick to simple and legible fonts and avoid using too many font sizes and styles.

Text Alignment

Reflowable formats such as EPUB allow readers to adjust the text size and style, making it crucial to ensure that your eBook's text is properly aligned. 

Avoid centering text as it can be difficult to read on some devices.

Pros and Cons of eBook Formats

Each format has its advantages and disadvantages, and understanding them can help you make an informed decision based on your content and target audience.

  • EPUB is the most popular and widely supported ebook format, making it a great choice for novels, fiction, and non-fiction books.
  • PDF is the best format for textbooks and technical manuals due to its fixed layout, ensuring consistent formatting across devices.
  • MOBI and AZW are compatible with Amazon's Kindle devices and apps, making them ideal for publishing on the Kindle store.

Thus, you need to choose the right eBook format depending on the type of content you're publishing, your audience and the devices you're targeting. 

That being said, here are some important pros and cons of each eBook format:



  • Open standard format that's widely supported
  • Reflowable text for better readability
  • Supports interactive features such as multimedia and hyperlinks


  • Limited support for fixed-layout content such as textbooks
  • Not compatible with Amazon's Kindle devices



  • Compatible with Amazon's Kindle devices and apps
  • Supports images, tables, and hyperlinks


  • Not compatible with other devices besides Kindle
  • Limited formatting options



  • Fixed layout that ensures consistent formatting across devices
  • Supports multimedia, annotations, and hyperlinks


  • Not reflowable, making it less flexible for smaller screens
  • Large file size that can slow down loading times



  • Compatible with Amazon's Kindle devices and apps
  • Supports images, tables, and hyperlinks
  • DRM protection for copyright protection


  • Not compatible with other devices besides Kindle
  • Limited formatting options

Frequently Asked Questions

1. What is the most popular ebook format?

EPUB is the most popular eBook format used worldwide.

2. Can I convert a PDF to EPUB?

Yes, there are various online and offline tools available to convert PDF to EPUB.

3. Which ebook format is best for textbooks?

PDF is the best eBook format for textbooks as it ensures consistent formatting across devices.

4. Is it necessary to add DRM protection to my ebook?

It's not necessary, but DRM protection can prevent unauthorized distribution of your eBook.

5. Can I publish an ebook in multiple formats?

Yes, you can publish your eBook in multiple formats to ensure compatibility across various devices.

Wrapping Up

Choosing the right eBook format is crucial to ensure that your content is accessible and readable on various devices. 

When formatting your eBook, keep in mind the basic principles of design and readability, such as using appropriate font sizes, spacing, and text alignment. Adding multimedia and interactive features can enhance the reading experience for your audience.

Finally, consider whether or not to add DRM protection to your eBook to prevent unauthorized distribution. While not necessary, it can help protect your content and ensure that you receive the appropriate royalties.

Suggested reading: ePub vs PDF

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Deepak Choudhary

Deepak Choudhary is the founder of Technicalwall.com. He is a Blogger and an Affiliate Marketing Expert. He publishes useful articles for newbie bloggers related to the following topics - Affiliate Marketing, Email Marketing, Software Reviews, Blogging, WordPress, SEO, Passive Income, and more.