UPDATE: see my latest tests on fonts here.

For those who read my blog post on the issue that has arisen with fonts embedded in ePubs, I make mention of using fonts for Kindle that are already licensed by them. The advantages to this are twofold: 1) You do not have to worry about procuring a font licence from the foundry that owns the font; and 2) not embedding fonts keeps your file size down, which is important as Amazon charge a delivery fee based on file size.

However…

The fonts licensed by Kindle and included in the Fire are:

• Georgia
• Caecilia
• Trebuchet
• Verdana
• Arial
• Times New Roman
• Courier
• Lucida (of which there are several and the one in Kindle appears to be Sans Unicode)

The new Kindle Paperwhite offers users the option to select:

• Caecilia
• Caecilia Condensed
• Baskerville
• Futura
• Helvetica
• Palantino

Older Kindles and the Kindle DX uses Caecilia only. The Kindle computer and mobile apps display the same as the Fire.

In order for the fonts to display as you wish, they must be included in the style definitions in your CSS. For example, if you are using 12 pt* Verdana in a style you call “Main,” Word will export to HTML something akin to the following (text is bolded for reference only), and other word processors or layout programs such as InDesign** will export their own version:

p.Main, li.Main, div.Main
{mso-style-name:Main;
margin-top:0in;
margin-right:0em;
margin-bottom:12pt;
margin-left:0in;
text-align: justify;
text-indent: 0em;
font-size:12.0pt;
font-family:”Verdana”,”sans-serif”;}

Because “Verdana” is included in the style definition, the Kindle Fire will display Verdana. If the font family is missing from your style, Kindle Fire will not know what font to display and will display the text in the font the user selects.

Similarly, because Verdana is not available in the Kindle Paperwhite, it will display the book in Caecilia, the Paperwhite’s default font (at least if Kindle Previewer is to be believed; I have not tested a Paperwhite device). Unfortunately, if you include a font definition that is not included in the device, not only will the Paperwhite display the text in the default font, but the user no longer has the option to override that and select their own font from those available.

Thus, if you want the user to be able to choose whichever font they wish to read your book in, do NOT include the font family in your style definitions, only the size (to differentiate between headers and text, for example).

If you DO want your ebook to display in the font of your choosing — a must if you use more than one font to differentiate between parts of your text — then you must include the font definition, and it must match exactly a font licensed by Kindle. Note that Word uses, for example, Lucida Sans Unicode, not Lucida; to get your ebook to display in Lucida on the Fire you would need to amend your the style in the HTML to read “Lucida.”

The change in fonts between the Kindle Fire/apps and the Paperwhite was, in my opinion, stupid on Amazon’s part. It has meant that consistency across its latest generation devices and apps is impossible unless we embed the fonts, something Amazon discourages us from doing, or so they say. Which leads me as a publisher having to conclude that consistency across the Fire and the computer and mobile apps is more important than how my book looks in the Paperwhite, and thus to use only the fonts included in the Fire/apps and to use font definitions in my styles where controlling the look of my book is essential. Otherwise, not including font definitions is the best way to go.

*When converted to an ebook, text size and margins et cetera are converted from points to ems and pixels, respectively.

**The Kindle plug-in for InDesign used to include font definitions when exporting to Kindle. The latest version, v0.973, does not unless you also embed the fonts. However, many users of InDesign prefer to export to ePub then convert to Kindle via Kindlegen. If you do, you should know that InDesign includes font definitions when exporting to ePub even where you elect not to embed the fonts themselves.