Even More Details about KENPC

Earlier this year, we released an update that addressed a lower-than-expected page count (KENPC) for eBooks listed with Amazon’s Kindle Unlimited. That change, detailed in a previous post, made page counts for eBooks created with Vellum comparable to eBooks formatted with other methods. However, we’ve recently received questions about a few eBooks that, when upgraded to use Vellum, resulted in a lower KENPC than before.

Providing an answer to these questions required some understanding of how KENPC is calculated. Many have wondered if KENPC is based on metrics like file size, character count, number of locations, or if it’s computed by analyzing the internal structure of files within an eBook.

After some tests, it seems that KENPC is computed in a manner similar to the page count of a physical book. The same factors that would affect a physical page count can change KENPC.

That means, for example, that specifying a large font for your eBook can actually increase the KENPC:

Book with normal font sizeBook with large font size
A book with a larger font size (right) can have a higher KENPC.

In our test, specifying a larger-than-normal font size increased page count by 25%. Greater line spacing, added paragraph spacing — essentially, all the tricks you learned to stretch the length of a term paper — can also be used to increase page count.

But it can go the other way, too: some styling changes can decrease KENPC. Changing text to use standard indentation and spacing creates a more professional result, but can lower page count (though typically by a smaller amount):

Book with large indentation and spacingBook with standard indentation and spacing
A book that uses standard, more professional typesetting (right) can have a lower KENPC.

These differences are, of course, something most thought shouldn’t happen with KENPC. The N in KENPC stands for normalized, and Amazon claims that KENPC calculations are “based on standard settings (e.g. font, line height, line spacing, etc.).” Unfortunately, that doesn’t seem to be the case.

We understand that KENPC affects income, and so we’ve debated adding options like a larger font size, or extra paragraph spacing. But we don’t think that’s the right choice. These options would produce less attractive books, create a poor experience for the reader, and ultimately harm all authors enrolled in Kindle Unlimited. So at this time, we are not adding any options solely for the sake of increasing KENPC.

We’ve heard rumors of improvements to Amazon’s KENPC calculations that would address these differences, and prevent authors from feeling like they need to choose between reader experience and additional income. We sincerely hope they pan out.

Update 2/1/16: Amazon has released KENPC 2.0.

Vellum 1.3

We’re thrilled to announce the release of Vellum 1.3, a major update that adds new publishing platforms, and makes it easy to create box sets.

Easily Create Box Sets

Making your work available in box sets is a great way to boost visibility and sales, and Vellum 1.3 includes many new features that help you to create them. Add existing books to your box set by dragging each Vellum document into Vellum’s Navigator. Use Vellum’s new Part and Volume elements to organize your book. And customize the placement and structure of your Table of Contents with Vellum’s powerful new settings.

Opening and closing a Volume in a book.

New Platforms

Many authors are choosing to maximize their exposure and sell in a variety of online bookstores. Vellum 1.3 builds upon its tailored output for Kindle, iBooks, and Nook by adding dedicated support for Kobo and Google Play.

Vellum generating eBooks for all platforms.

More Features

Vellum 1.3 has a great many more features and fixes. Here are just a few:

  • Write books in foreign languages, with automatic chapter numbering for German, Spanish, French, and Italian
  • Change indentation, hyphenation, and justification in the new Body Style Editor
  • Customize the font used in the Text Editor
  • Output Generic EPUB for smaller stores and aggregators

Download Now

Vellum 1.3 is a free update, available now.

If you don’t already have it, you can download Vellum from vellum.pub.

Update 10/5: We’ve added a new help page for Creating Box Sets.

More Details about Vellum and KENPC

After the recent release of Vellum 1.2.5, we wanted to provide a bit more detail about the change we made that affects books available through Kindle Unlimited.

As we mentioned in the announcement, Vellum 1.2.5 addressed concerns we heard from authors who reported receiving a lower-than-expected page count (KENPC) when using Vellum.

Amazon does not provide any information about how KENPC is calculated, but instead assures that it is “based on standard settings (e.g. font, line height, line spacing, etc.)” Unfortunately, as many authors have discovered, this isn’t true in practice. We’ve seen a lot of speculation about these calculations, and so we thought it was best to share specifically what we changed.

For Vellum’s output for Kindle (only), we removed the specification of the “line-height” property, which affects the spacing between lines of text in the book. If you are familiar with CSS, we essentially made this change:

p {
    margin-top: 0;
    margin-bottom: 0;
    text-indent: 0;
    line-height: 1.4em;

That’s it. And while this resulted in some issues with our drop caps, causing us to adjust other aspects of our CSS in response, it should make very little difference (if any) to file size and delivery costs.

This fix was actually discovered and tested by some of the very authors who first contacted us. Because they could confirm that the change addressed their KENPC discrepancies, and because Amazon’s most recent guidelines advise against declaring line-height for main text, this seemed like the right change to make.

We don’t know whether Amazon is intending to penalize authors who specify a line-height, or whether it’s just a bug in their KENPC calculations (See update below). But given their promises of a “normalized” page count, we think it’s a flaw that KENPC is at all affected by formatting.

Again, our motivation was simply to eliminate the discrepancy authors reported when comparing other formatting methods. We have no interest in further optimizing KENPC, or gaming Amazon’s calculations. We sincerely hope that Amazon delivers on their promise of a page count that is actually normalized.

And while that may happen in a future implementation of KENPC, we didn’t feel like this was something we could wait on. We heard from authors who felt that they couldn’t continue to use Vellum if it resulted in a lower KENPC, and we didn’t think this was acceptable.

We’d like to thank the generous and patient authors who reached out to us, helped find a solution, and then tested our fix in Vellum. And we look forward to when authors can spend more time writing and less time fretting over KENPC. Until KU 3.0, anyway.

Update 10/8: Further testing has indicated that this was likely because a 1.4em line-height is smaller than Kindle’s default, and that a value larger than the default would have resulted in an even higher KENPC. Given this potential fluctuation, as well as the reasons above, we still believe that removing the line-height declaration is the best answer.

See also: Even More Details about KENPC.

Kindle Unlimited & Vellum 1.2.5

Recently, Amazon changed royalty calculations for books available through Kindle Unlimited (and Kindle Lending Library) to be based on number of pages read. These calculations are determined using a normalized page count, or KENPC, that is intended to be independent of how the book is formatted.

We’ve received feedback, however, that eBooks created with Vellum sometimes reported a lower KENPC than eBooks created through other means. In response, we’ve released Vellum 1.2.5, which adjusts output to no longer produce these lower KENPC numbers.

If you have a book you’d like to update, simply open it with this newest version of Vellum and re-generate. No other changes are necessary.

Vellum 1.2.5 is available now for Direct users, and has been submitted to the Mac App Store for approval. You can learn more about updating from our Tips Page.

Update 7/31: See also More Details About Vellum and KENPC.
Update 8/4: Vellum 1.2.5 is now available from the Mac App Store as well.

Vellum 1.2.4

Last week, Barnes & Noble relaunched their website with many changes. Unfortunately, some of these changes have broken links to book titles, including those created by Vellum with Store Links.

In response, we’ve released a small update. Vellum 1.2.4, available today for Direct users, will generate links that work with the new Barnes & Noble site.

If you have a book you’d like to correct, simply open it with this newest version of Vellum and re-generate. No other changes are necessary.

Vellum 1.2.4 is available now for Direct users, and has been submitted to the Mac App Store for approval. You can learn more about updating from our Tips Page.

Update 7/10: Vellum 1.2.4 is now available from the Mac App Store as well.

Three Myths about Amazon Delivery Costs

Calculating Delivery Costs for books sold through Amazon KDP is not at all straightforward, and has given rise to a complex mythology about file size.

Here, then, we hope to dispel three myths about KDP Delivery Costs.

MYTH: Delivery costs are assessed on the file you upload to KDP.

TRUTH: Delivery costs are based on a smaller version of your book that is contained in the mobi file you upload.

The mobi file you create with Vellum actually contains multiple versions of your book, and can therefore seem large. Delivery Costs, however, are only computed on a single version within. This version is designed for legacy Kindles and is much smaller than the file that contains it:

Comparison of mobi size and delivery cost size

MYTH: Using higher-resolution images significantly increases KDP Delivery Costs.

TRUTH: It’s the number of images in your book, and not their resolution, that will most affect Delivery Costs.

One reason the legacy version is smaller is that it uses compressed versions of the images in your eBook. These lower-resolution images are automatically created by Vellum (via KindleGen). So, while adding images to your eBook will increase Delivery Costs, the resolution of your images in Vellum will have very little effect. To ensure your book looks its best on newer Kindles, we recommend using the highest-resolution images available.

Comparison of sizes with medium and high-resolution images

MYTH: Using custom fonts for headings and drop caps increases KDP Delivery Costs.

TRUTH: Custom fonts do not increase Delivery Costs at all.

Custom fonts embedded in the .mobi file do increase the overall size. However, these fonts are excluded from the legacy version, and therefore have no effect on Delivery Costs.

Comparison of sizes with standard and embedded fonts

As always, we recommend referring to KDP to evaluate the Delivery Costs for your book. After you upload, look for file size after conversion on your book’s Rights & Pricing page. As noted in Amazon’s Pricing Information, Delivery Costs are only applicable when selecting the 70% royalty option, and do not apply when electing to receive a 35% royalty.

For more information, see our help page about File Size Considerations, or feel free to send a question to vellum@180g.co.

Vellum 1.2.3

Today we released a minor update to Vellum that contains the following fixes:

  • A recent Amazon update for Kindles changed the way that text wrapped around floating images. This update to Vellum restores the desired formatting.
  • The context menu in Vellum’s Text Editor now displays possible spelling corrections for the selected text.
  • Alignment Blocks now work in all elements, even Copyright and Dedication.
  • Fixed bug where sometimes images wouldn’t be copied to the clipboard.

Vellum 1.2.3 requires OS X 10.9 (or newer) and is a free update. It is available now for users of the Direct version of Vellum, and has been submitted to the Mac App Store for approval.

If you don’t already have it, you can download Vellum from 180g.co or from the Mac App Store.

Update 2/16: Vellum 1.2.3 is now available from the Mac App Store as well.

Vellum 1.2.2

We’re excited to announce Vellum 1.2.2, the most major minor update yet! It includes the following, much-requested features:

Alignment Blocks allow you to center selected blocks of text, or render them flush left or right.

A centered Alignment Block in Vellum's iPad Preview

More authors are telling us that they have chosen to write entirely in Vellum. Our new Export feature makes it easy to use the text of your book in other applications – like Microsoft Word, Pages, and others – if necessary.

Export to RTF menu item

In addition, we’ve added a bunch of fixes and other small improvements, including:

  • The appearance of a book’s title page and chapter headings has been improved when viewed in Amazon’s Look Inside
  • Images used within an iBooks file can now contain up to 4 million pixels
  • Long sections of Verse no longer cause a large expanse of blank space
  • Chapter headings better adapt to the iPhone 6
  • The value for “Display Heading in Book” is now saved correctly
  • Inline images are now included when printing a manuscript

Vellum 1.2.2 requires OS X 10.9 (or newer) and is a free update, available now.

If you don’t already have it, you can download Vellum from 180g.co or from the Mac App Store.


Vellum 1.2.1

Vellum 1.2.1 is now available. Included in this bug-fixing and stability release:

  • Dictation can now be used in the Text Editor
  • Copying/pasting is more reliable for both images and text
  • Improved legibility of Artisanal Book Style
  • Tall, full-sized images now fill available space on Kindle and iBooks
  • Fixed bug that caused occasional artifacts in Preview
  • Long chapter numbers are no longer truncated in the Navigator
  • Addressed rare crash during eBook generation
  • Clicking in the lower section of the Text Editor now works consistently

If you haven’t configured Vellum to update automatically, here’s how to update now: Tips: Updating Vellum.

Include Images in Your Books with Vellum 1.2

We’re extremely excited to announce the release of Vellum 1.2, a major update that adds the ability to include photographs, illustrations, and any other kind of image in your eBooks.

iPad and Kindle showing example pages with images

Now you can create beautiful eBooks in even more genres. With images, you can:

  • Show the map of a world in a fantasy novel
  • Enhance a memoir with historical photographs
  • Augment a reference book with screenshots and diagrams
  • Add illustrations to a story for young readers

Vellum takes the notoriously difficult problem of using images in eBooks and makes it easy. Just drop images into your book and use Vellum’s simple controls and immediate Preview to achieve the look you desire. When it comes time to generate your eBooks, Vellum automatically resizes and reformats images to satisfy the complex requirements of each store.

Vellum 1.2 is a free update, available now. If you don’t already have it, you can download Vellum from 180g.co or from the Mac App Store.