See How We Work

Reviewing Your eBook Files

eBook Quality Assurance is a very important part of every eBook creation process. This page will give you instructions on how to install the programs you’ll need, review your files, and send us any revisions you encounter.

Installing Programs and Viewing Files

Once you are finished downloading the eBook files to your computer, it is time to look them over. We encourage you to load the files onto eBook devices like the Kindle, Nook, and iPad (in iBooks) if you have those available, but you can also use some specific computer programs for this reviewing process if necessary.

Because the MOBI and ePUB files are different formats, we will discuss them individually in the sections below.

Fixed Layout eBooks

Please note that fixed layout eBooks (whether children’s or other types) can only be viewed in specific applications. Trying to load a fixed layout title in other devices or applications will not show you the proper formatting your readers will see when they buy the eBook. Here are the devices/apps you should use for each retailer:

For information on how to load files into these reading systems, please follow the instructions below.

The MOBI file

The .MOBI file is the format used on Amazon’s Kindle platform. The best option for viewing a Kindle eBook is loading it onto a Kindle device. To upload the file to your Kindle device, please use Amazon’s Kindle Personal Documents Service.

If you do not have a Kindle device, you can use your computer to review your Kindle file. While Amazon does have Kindle applications for the PC and Mac, the best program to view your Kindle file is Kindle Previewer. This application is provided by Amazon expressly for the purpose of reviewing Kindle eBooks, and it does a good job of emulating how the file will look on all of the Kindle devices and apps. To install this tool on your PC or Mac computer:

  1. If you’ve not done so already, download the Kindle Previewer:
    • Go to this web page.
    • Check off the box to accept the terms of use.
    • Download the correct installation program to your computer.
    • Follow the instructions to install the software.
  2. Once the program is installed, open it (it will be in your Programs list).
  3. Open the Kindle file by dragging and dropping it into the open program window or by using the Open option on the Kindle Previewer home screen.
  4. The controls and menus at the top of the program window allow you to turn pages, skip to chapters, change the font size, and switch which device you are emulating. The most important devices to test on are the Paperwhite and the Fire.

KDP Previewer: Please note that the Preview option on Amazon’s KDP platform does not do as good a job of showing you what your eBook actually looks like as Kindle Previewer does.

Kindle for iPad App: The Kindle for iPad application does allow loading files for testing, but you have to load the file in a very specific way.

  1. Before you begin, you must check the version number of Kindle for iPad. You will find the version number in the app under Settings > Other > About. You must have version 3.9.2 or greater installed in order to do this testing.
  2. You also need to have the latest version of Kindle Previewer installed on your computer (2.91 or later).
  3. Open the .mobi file you received from us in Kindle Previewer.
  4. Under the Devices menu, choose Kindle for iOS.
  5. Kindle Previewer will open a dialog saying that it is converting your file to the .azk format.
  6. When the process is complete, you will see the new .azk file in the same folder as your .mobi (or use the link in the pop-up to find it).
  7. Open iTunes, connect your iPad to your computer, and navigate to the iPad summary page in iTunes.
  8. Click on the Apps tab at the top of the iTunes window, the scroll down on the screen (under the apps list) until you see the File Sharing section.
  9. Select Kindle from the list, the either drop your .azk file into the list on the right or click the Add button and add it that way.
  10. Once you have completed that process, the book should show up in your library in the Kindle for iPad app.

Please note that the Kindle for iPad app has many limitations and bugs that are not fixable in the Kindle file. Kindle Previewer and the Kindle devices are the primary locations you should test your Kindle file. If something looks different in the iPad app it is almost guaranteed to be a limitation of the app, not the eBook.

Also, please note that the .azk file is only for testing purposes. You should always deliver the .mobi file we create to Amazon. It will be converted in their system to work in the iPad app.

If you see anything that needs to be changed in your file, please see the section below for information on reporting revisions to us.

The ePub file

ePub is the industry standard eBook format, so it can be viewed on a variety of devices and in many software applications. Those devices and applications typically use one of two display engines to show you the content of the ePub file: Adobe or Webkit. The Adobe display engine has not been updated to take advantage of all of the new features available in ePub files today, so there will be some things that may look less appealing in Adobe-based devices and applications than in a Webkit-based device or app.

For reviewing your ePub file, we recommend you look at the file on actual devices. Whether that is a tablet or an eInk device, you will usually be able to more easily see what your readers will see when they purchase your eBook if you use a device.

In iBooks on an iPad

If you have an Apple iPad/iPhone/iPod Touch, you can view your ePub file in a variety of software applications on the device. The most important app to review your file in is the iBooks software from Apple. If you do not have iBooks installed on your iPad you can download it for free from the iTunes App Store. Once iBooks is installed, you can add the ePub to your iTunes library choosing File > Add to Library, or drag the ePub file to the Books library in iTunes on your computer.

On a Nook/Kobo/Sony

Most devices like the NOOK, Kobo, and Sony Reader allow you to “sideload” the ePub file directly to your device by connecting it to your computer and copying the file into a folder. For information on this process, please see the following help pages.

On a computer

If you do not have a device, you can use one of a few programs on your computer to view the ePub file.

If you are running the latest version of OS X (Mavericks), the best program to use for reviewing your eBook is iBooks for Mac. This desktop version of iBooks comes pre-installed in OS X Mavericks, so there is no need to install it separately.

For other computers, the most up-to-date program, and the one we recommend you use for your previewing, is the Readium plugin for Chrome. You must have the Chrome browser installed in order to use Readium.

The most common program people use when looking at ePub files on a computer is Adobe Digital Editions (ADE). ADE does not have every good support for newer ePub features, so you may not see the same formatting in ADE as you do in better reading systems like Readium. To install the ADE software on your computer, visit the ADE website, then download and install the program. When the program opens you can choose to register it with an Adobe account, or you can leave it unregistered. To open your ePub file, you can either double click on the file (ADE installs as the default ePub reading program on your computer) or click on the Library dropdown and select Add item to Library.

On other devices

On other devices (such as Android tablets), we recommend installing and using applications from Amazon, B&N and other retailers in your testing.

Submitting revisions

As you are looking over your files, you may find some things that you would like to have us change, or errors that were somehow introduced into the files during the conversion process. We are happy to make changes to your files at any time, even if you find something that is wrong after the file has been published.

Please provide us with the following information for each revision you submit:

  1. The source page number: On more extensive or complex changes, it is nice to have the PDF, Word, or print book page number so that we can compare the eBook to the print book in that place. This is not absolutely necessary, though, as long as we have the unique, searchable text that will let us find the spot.
  2. The eBook format the revision applies to.
  3. Searchable text: We will be making your changes in the XHTML code, not in the original PDF/Word file, and the easiest way to find places in the XHTML code is to search for them. So, please give us some unique, exact, searchable text that we can use to find the exact spot of the issue in the book. Some examples:
    • the word that was misspelled
    • The first few words of the nearest paragraph or heading (for issues with images, formatting, etc.)
    • The caption text (for issues with images, charts, tables, etc.)
  4. A good description of the error: This does not have to be long, but it should be precise. This can also be combined with the searchable text if that makes sense. Some examples:
    • “missppelledd” should be “misspelled”
    • Change “The red fox jumped over the lazy dog” to “The purple cat jumped over the jumping giraffe”
    • Move the image of the mountain above the paragraph that starts “When we moved to Colorado…”

Types of Revisions

Changes that our clients normally want to make to their eBooks usually fall into one of three categories:

  1. Our errors: While the processes we use to extract text from original files are the best in the industry, that extraction process is not always perfect. In addition to thorough proofing and spell checking, we also run multiple algorithms against the code and the text in an attempt to catch anything that might have been messed up by the process. Our developers do not proofread the text word-for-word against the source files for exact accuracy, but they are always looking for errors and issues as they format and test the eBook files.
    If you find errors that were introduced by our process, such as OCR/typing errors, missing hyphens, incorrect or misplaced images, or missing basic formatting like italics and bold, those changes will always be fixed promptly and at no cost to you.
  2. Editorial changes: Many of our clients will catch small errors in their print book files before, during, or even after our eBook development process. We charge $150 per hour to make editorial changes in the eBook files. There are also times when re-doing the eBook process from new source files makes more sense than trying to make a huge number of editorial changes. If you think that might be the best approach, please let us know.
  3. Formatting changes: Because of the differences between eBooks and their print counterparts, and because of the limitations of some eBook formats, there will be places in an eBook that are not designed the same as they are in print. We do our very best to match the print design and to use comparable design features in the eBook formats. However, we have worked with some clients who are very design-oriented themselves, and they want to have much more control over the design of the final eBook product. In cases like this, we are more than happy to make reasonable changes to the design of the eBook files to match the desires of the client. However, there comes a point when that process is no longer about making reasonable changes and it becomes a complete re-design of the eBook.
    At that point, we will set up a phone conference with you to discuss what you are interested in doing. All of these design processes are charged our standard $150 per hour development fee. It is important that you understand the limitations of the eBook formats and that you be willing to be flexible as we work out design options for your eBook that will work on the different platforms you are targeting. We are also happy to talk with you about these limitations before we even start the eBook creation process so that you enter the process informed and prepared. It is definitely easier to do these design adaptations as part of the original process than to do them later.

If you have any questions about this or anything else, please do not hesitate to contact us.


Is it a good idea to put my Table of contents at the end of my eBook?

Some people do this to increase the size of the free samples automatically generated by the eBook retailers. However, the Kindle and other devices will re-set the “last read location” to the end of the book if you have your Table of Contents there, so we normally recommend against that practice.

What is the difference between HTML5 and XHTML5?

HTML5 is the latest version of the HTML standard used on the Web and in eBooks. XHTML5 is a stricter and cleaner version of HTML5, with rules from XML imposed on the code. For example, when a tag is opened it has to be closed, and all of the tags have to be properly nested. XHTML5 allows the code to be more easily interpreted by the display engine, and it keeps the code more consistent and easier to edit.

I have heard you can’t use color in eBooks. Is that correct?

No, that is absolutely incorrect. eBooks look great with color, and we highly recommend using color images and even colored text (within reason) in your eBook files. Some devices have grayscale eInk screens, so the color will not show up on those devices. However, the color will be in the file, and it will work on all of the color devices. We do recommend you test colored text on a device with an eInk screen and ensure that the text will not be too light to read.

Do you need to have a separate ISBN for each version of the eBook for different companies?

Technically, yes. See an extended answer on our ISBNs page.

What is KindleGen?

KindleGen is Amazon’s eBook creation/compiling program. It is used on the KDP website to auto-convert files uploaded into the Kindle store, and it is also integrated into the Kindle Previewer program to handle the conversion of non-Kindle files loaded in that program. You can download KindleGen and get access to other Kindle creation information at

What is a fixed layout eBook?

Fixed Layout eBooks are HTML-based eBook files that are usually designed to match the layout of a print book. The key difference between fixed layout files and reflowable files is that reflowable eBooks allow the reader to have more control over the reading experience, such as changing the font size, background color, etc. For more information, please see our Fixed Layout Children’s and Non-Fiction pages.

Does Amazon sell HTML files or only Kindle?

Amazon only sells eBooks in the Kindle format, but that format, just like ePub, is built using HTML and CSS files.

How is fixed layout different from a pdf of the book?

Fixed layout eBooks are built using HTML, so they have more functionality than PDF files. For example, the narration overlay functionality used in many children’s eBooks is not possible in PDF files. In addition, none of the eBook retailers sell PDFs, so fixed layout eBook files offer the best sales opportunities.

A university librarian told me they are not acquiring any Kindle books but only HTML5/ePub. Have you found that to be common with other libraries? I know our local public library does buy Kindle books.

Libraries acquire their eBooks from services like 3M and Overdrive. These services sometimes offer an option for Kindle checkouts, but typically they are limited to ePub files because of the more common use of the Adobe DRM.

Has the Kindle format gotten any more sophisticated in how it handles tables or floating images?

Yes, Amazon’s Kindle Format 8 has support for many great design features, including floating images, tables, color text, embedded fonts, and more.

How are page numbers handled in an eBook?

Print book page numbers are included in the HTML code of both the Kindle and ePub formats as anchors. They are also listed in the PageList section of the NCX or Navigation file. The PageList is used by some reading systems (like the Kindle and iBooks) to show the reader the print page numbers of the book as they read.

How are page headers created in eBook files?

The different reading systems control what shows up in the header of your eBook. Most will display the title of the book, and some will also display the author name. That text cannot currently be set to display the chapter name or other information about where the reader is currently reading in the text.

How do eBooks handle hyphenation of long words?

Some eBook reading systems will apply hyphenation to longer words to make the text better fit on the screen. This is typically controlled by the reading system, and will change depending on the font size and other settings the reader has set on their device.

What about protecting the file?

eBook file protection is called Digital Rights Management (DRM). Please see our DRM page for information on how it works and suggestions on how to use it.

Can I sell my eBooks on my own website?

Yes! You are certainly able to sell your eBooks on your own website. For more information, please see this page.