Making an ebook accessible

An ebook is the most accessible long-form reading format ever invented — when it is built honestly. The format reflows to any screen and any type size, screen readers can read it aloud, and fonts can be swapped for dyslexia-readable ones at the reader’s whim. Every one of those abilities depends on the same thing: the file saying what it contains, structurally, instead of just showing it.

An accessible EPUB is a well-structured one, and the overlap between “accessible” and “good” is nearly total. That is most of the everyday work for a text-heavy book — formal EPUB Accessibility conformance adds a wider set of WCAG checks and accessibility metadata on top.

What the reader’s tools need

Assistive reading is a set of tools, each with one requirement:

Screen readers speak the book aloud. They need real text — not images of text — in a sane reading order, real headings to navigate by, and alt text for images. A screen reader user reads a novel by chapter headings the way a sighted one skims by them; headings that are just large bold paragraphs are invisible to the navigation.

Reflow is the reflowable EPUB’s native gift, and the reason a fixed-layout book abandons it: the reading system re-paginates the text at whatever size the reader chooses. Magnification is separate — a capability of the reading system or the operating system — but it, too, assumes the text is real text.

Text adaptation — dyslexia fonts, larger spacing, different colour themes — works best when the content stays real text in a reflowable layout. CSS styling is fine; that is how the format is meant to work. The problems begin when presentation is baked into images, fixed positioning or other constructs the reading system cannot adapt.

Text-to-speech, built into most devices, has the same needs as a screen reader.

The common thread: every tool takes over the presentation, so the file must carry the meaning. Presentation-only books — big bold paragraphs, text baked into images — defeat all of them at once.

The practices, in order of value

1. Real headings, in order. Chapter titles are headings, section titles are subheadings, and the levels nest without skipping. This is the single highest-value change and the cheapest: it is the difference between a screen reader user navigating a book and page-turning through it. It is also the same structure the table of contents is generated from — one structure, two consumers.

2. Alt text on meaningful images. What the image contributes, not what it looks like: “map of the eight parishes of Jersey” beats “map”. Decorative images — ornaments, flourishes — take empty alt text, because describing them is noise. Charts and diagrams carry their content in words; the reader who cannot see the graph still needs the trend it shows.

3. A navigable table of contents. The navigation document is how assistive and ordinary readers alike move through the file. EPUB 3 requires one; accessible-publishing guidance asks for adequate navigation to the book’s major sections and top-level headings, under their real names.

4. Text as text. No pages as images, no pull quotes rendered as graphics. This is the failure that no amount of alt text repairs: a page that is a photograph is a page a screen reader cannot read at all.

5. Reading order. The file’s internal order should be the reading order. EPUB’s structure makes this natural; it breaks when layout hacks — positioned boxes, layout tables — are used to simulate design, and the screen reader then reads the book in construction order, which is gibberish.

6. Honest semantics throughout. Lists marked as lists, quotations marked as quotations, tables with header rows. Each is a one-line cost at build time and a continuous benefit in use — the screen reader announces “list of five items” instead of bullet characters with no context, and semantic quotation marks expose the boundary between a quotation and the author’s voice. Exactly how each reading system announces these varies; the point is that the meaning is there to be announced.

7. Accessibility metadata. The EPUB should state what forms of access it supports, its accessibility features and hazards — and, when a formal conformance claim is being made, the standard and level it meets. EPUB Accessibility 1.1 defines this metadata precisely, and it is what lets bookstores, libraries and readers discover whether an edition will work for them.

What it costs

Far less than it appears, when the book is built from structure — because most of the practices above are by-products of the same decisions that make an EPUB robust everywhere. Retrofitting a presentation-built file is the expensive path: images of text re-typed, headings re-marked, a navigation document reconstructed.

Real work remains even in a born-accessible workflow: writing the alt text, evaluating the result — automated checks and, for anything beyond simple text, manual testing — and getting the metadata right. The honest summary: born accessible is dramatically cheaper than retrofitted, and it is not free.

Why the pressure is growing

Three forces, none of them charitable:

Law. The European Accessibility Act covers e-books provided to consumers in the EU from 28 June 2025. It requires accessible structure and presentation, interoperability with assistive technologies, accessibility metadata that makes the features discoverable, and DRM that does not block accessibility. The exemption is for microenterprises providing services — fewer than ten employees and turnover or balance sheet under €2 million — and separate provisions allow a disproportionate-burden or fundamental-alteration argument where its conditions are met. There is no exemption simply because a book is self-published. In practice, some retailers and library platforms ask publishers to declare accessibility information at setup or display it on the product page.

Purchasing. Libraries, school systems and corporate buyers increasingly specify accessible editions, and the metadata for declaring accessibility is becoming part of the distribution checklist. A book that cannot say what it supports is harder to buy for exactly the institutions most likely to want it.

Market. The readers who need these features are a large and often underserved population — the same population large print serves in print — and accessibility metadata makes a book findable to them, which it otherwise is not.

The economics are the reverse of the print world’s: an accessible EPUB and an inaccessible one are built from the same text at nearly the same cost, and one of them is invisible to a growing share of the market.

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Accessibility in an ebook is the structural honesty the format has always rewarded: say what things are, keep text as text, let the reader’s tools do their work. It is also, quietly, the same craft that makes an EPUB behave well on every device — the two goals were never in tension.

Nueel builds the accessible edition by default, and checks it rather than assuming it: real headings from the book’s structure, a generated navigation document, semantic quotations and notes, and alt text carried with the image. The accessibility metadata EPUB Accessibility 1.1 defines is written into the package, and Ace’s package-level rules are re-run on the file before it leaves — so the conformance the metadata claims is verified, not hoped for.

Sources

• W3C, EPUB Accessibility 1.1
• DAISY, Accessible publishing knowledge base — decorative images, images of text, reading order
• KDP, Accessibility guidelines and Accessibility for eBooks
• European Union, Directive 2019/882 (European Accessibility Act)

Common questions

What makes an ebook accessible?

Structure the technology can read: real headings instead of styled text, alt text on images that carry meaning, a navigable table of contents, a correct reading order, and text kept as text. A book built that way works with screen readers, dyslexia-friendly fonts, text-to-speech and magnification — because the format reflows, and the reader's tools can take over. Formal conformance adds WCAG checks and accessibility metadata on top.

How do I write alt text for book images?

Say what the image contributes — often a sentence or two, with no universal length limit. A diagram's alt text carries its content: 'line graph: sales fall 40% between March and May'. A complex chart or map may need a longer description in the surrounding text. A decorative ornament takes an explicitly empty alt attribute, because describing it adds noise for screen reader users. The test is: if the image were removed, what would the reader lose?

Is accessibility legally required for self-published ebooks?

The European Accessibility Act covers e-books provided to consumers in the EU from 28 June 2025: accessible structure and presentation, compatibility with assistive technologies, accessibility metadata, and DRM that does not block accessibility features. The exemption is for microenterprises — businesses with fewer than ten employees and under €2 million turnover or balance sheet — not for self-published works as such. Some retailers and library platforms also ask publishers to declare accessibility information in the file's metadata.

Does an accessible ebook look different?

Almost never. The changes are structural, not visual: a heading is still displayed large, but it is marked as a heading; a list still has bullets, but it is marked as a list. Accessible typography and attractive typography are the same practice — the difference is that one of them also tells the machine what it is looking at.