Fix for Distorted Italic and Bold Text in EPUB Export from InDesign

[stiano]

Italic type and boldface type gets scrunched (especially when there is punctuation) when I export to EPUB from InDesign. Any fixes that don't involve going under the hood into CSS and coding?

Thank you.

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[James Gifford—NitroPress]

What format are you exporting to? I'm assuming fixed-layout; if so, there are not many easy fixes for faulty export.

But details on the project are essential to narrow things down. ID version, platform, format, fonts? And perhaps most importantly, what EPUB viewer are you using?

[stiano]

Thanks for answering.

I'm exporting from InDy 2025. Yes, fixed-page layout. On a Mac Studio running Sequoia 15.1 OS. The fonts are Adobe ScalaPro and ScalaSansPro. I'm using Apple's Book's app on the Mac Studio to view as I work.

[James Gifford—NitroPress · Accepted solution]

Nothing jumps out except the format. A poor EPUB reader can be one problem, as can use of variable fonts. But as so often, FXL itself is a problematic format at best, with the problems multiplied when used for text-page output. It's also not InDesign's strongest feature.

One short answer is that if you must have print-replica pages, use PDF. It's what it's for and it works almost perfectly. EPUB is at its best with reflowable text content or a narrow range of "picture page" formats; exporting text pages to fixed layout is fraught with problems and usually unsatisfactory.

The Apple viewer is somewhat nonstandard but not bad. You might try viewing the exported file on a more standard viewer such as Thorium or Calibre; if it views correctly on those, or at least loses the font problem, it narrows things down.

The fonts seem okay as a choice (not variable or otherise nonstandard). But fonts in EPUB are... a whole other area of problem. If you're using anything but the base four fonts (regular, italic, bold, bolditalic) the format and reader may not be processing them well; you can't, for example, use alternates like light or semibold or black in reflowable EPUB. (Not easily and without faults, at least.)

The only start on a solution would be to make sure your use of styles (paragraph an character) is spotless and without any spot overrides or local formatting. No matter what else it is, EPUB is absolutely reliant on technical source perfection, and things you can get away with in print (or PDF) will blow up in a digital export.

But mostly... it's likely to just be FXL's limitations, unsuitability to text documents, and InDesign's indifferent export function. A switch to PDF (if you have to have fixed pages) or reflowable EPUB (if you must have EPUB) may be the only options.

[stiano]

Thanks. I've been leaning toward PDF. I've done interactive PDFs before. I'm just unclear on whether PDFs can be read on Kindle readers. This matters to my client.

Thanks again.

[James Gifford—NitroPress]

One thing that occured to me, hours later and not near a console, is that ALL export from InDesign handles spot formatting poorly, especially bold and italic applied using the spot-apply key assignments or that imported from Word. Rereading your post and noting the problem is mostly with bold and italic... I'd start by making sure all your highlights are clean Character Styles, not spot overrides.

[James Gifford—NitroPress]

In theory, PDFs can be side-loaded to Kindle. In practice, it's not the best approach.

Keep in mind that no matter what KDP/Kindle/Amazon claims, KDP readers read ONLY Kindle formats. They made a big deal about "Kindle reading EPUB" a year or so back... which is sort of true, except that your side-loaded EPUB is silently converted to an undocumented format.

Kindle is for Kindle. I would not try to use it for any other format, especially with the relatively difficult process of sideloading docs. I would not count on any interactive features, even links, to work under such a path.

[Laura Brady]

If you are exporting fixed-layout (which I think you may be from hints in other posts) then the issue is very likely tracking. The CSS for FXL is not good at respecting letter- or word-spacing in the transition from layout to digital. Fixing it can be a real pain but involves using letter-spacing CSS such as letter-spacing:.01em; etc,  

[stiano]

As I said on another thread with, essentially, my same concerns, the client and I are going interactive PDF.

[James Gifford—NitroPress]

Well, that may be frying pan into the fire. 🙂

While FXL EPUB is... effectively obsolete except for a niche range of uses, PDF with any features much besides internal links is something like EPUB in that it's highly dependent on the reader used. There is no assurance that interactive features — sometimes even those internal links — will work in anything but genuine Acrobat. So if you are creating documents for use by a general readership, who may use any third-party reader or (most likely) the very underpowered readers built into mobile devices or browsers, you're not going to have a very happy conclusion.

The only reasonably stable platform for interactive documents, especially things like forms or ones using multimedia elements, is HTML/web.