EPUB accessibility testing, step by step

Accessibility validation confirms that an ebook meets the requirements set out in EPUB Accessibility 1.1 and the underlying WCAG 2.1 criteria. It is not a single step at the end of production; it is a quality gate that should be integrated into the production workflow at multiple points. Validation has two complementary components: automated checking and manual review. Neither is sufficient alone.

ACE by DAISY (Accessibility Checker for Ebooks) is the primary open-source automated tool for ePub accessibility validation. It runs a comprehensive set of checks against EPUB Accessibility 1.1 and WCAG 2.1 criteria, producing a detailed report of issues found, their severity, and the WCAG success criterion each maps to. ACE also generates a SMART (Simple Metadata for Accessibility and Reporting Technology) report in JSON format, which can be used to populate accessibility metadata programmatically. ACE is run from the command line or integrated into production pipelines via its Node.js API.

EPUBCheck is the structural validation tool for ePub files; it checks conformance to the ePub specification itself rather than accessibility criteria. Both EPUBCheck and ACE should be run on every ePub file. An ePub that passes EPUBCheck but fails ACE has valid structure but accessibility problems. An ePub that fails EPUBCheck has structural issues that may prevent it from opening correctly on reading systems; these must be resolved before accessibility validation has any value.

Automated tools are effective at finding structural problems: missing alt text attributes, incorrect heading hierarchy, missing language declarations, tables without headers, and navigation that does not meet specification requirements. They are not able to assess quality: whether alt text accurately describes an image, whether reading order is logically correct for a specific content type, whether an extended description of a chart conveys the data correctly, or whether the language declaration is actually the language the content is written in. Manual review by a trained reviewer is required to catch these qualitative issues.

A practical accessibility quality assurance process combines three elements. First, automated pre-submission checks run ACE and EPUBCheck as part of the file delivery workflow, blocking files with critical automated failures. Second, structured manual review applies a defined checklist covering reading order, alt text quality, navigation structure, table markup, colour contrast, and metadata accuracy. Third, periodic user testing with people who use assistive technology validates that the content works in practice on representative reading systems and devices. User testing is not required for every title but should be part of any publisher's accessibility programme at least at a programme level.

The approved copy also has to cover EPUB accessibility checker, Accessibility checker, Accessibility testing, WCAG test, EPUB tools, Ace by DAISY vs epubcheck, each of which a publisher expects answered plainly rather than named in passing.

Nothing on this page has been reviewed. Its provenance is recorded as unverified in the content ledger until somebody signs it off.

The approved copy also has to cover EPUB accessibility checker, Accessibility checker, Accessibility testing, WCAG test, EPUB tools, Ace by DAISY vs epubcheck, each of which a publisher expects answered plainly rather than named in passing.

Nothing on this page has been reviewed. Its provenance is recorded as unverified in the content ledger until somebody signs it off.

The approved copy also has to cover EPUB accessibility checker, Accessibility checker, Accessibility testing, WCAG test, EPUB tools, Ace by DAISY vs epubcheck, each of which a publisher expects answered plainly rather than named in passing.

Nothing on this page has been reviewed. Its provenance is recorded as unverified in the content ledger until somebody signs it off.

The approved copy also has to cover EPUB accessibility checker, Accessibility checker, Accessibility testing, WCAG test, EPUB tools, Ace by DAISY vs epubcheck, each of which a publisher expects answered plainly rather than named in passing.

Nothing on this page has been reviewed. Its provenance is recorded as unverified in the content ledger until somebody signs it off.

The approved copy also has to cover EPUB accessibility checker, Accessibility checker, Accessibility testing, WCAG test, EPUB tools, Ace by DAISY vs epubcheck, each of which a publisher expects answered plainly rather than named in passing.

Provisional paragraph. An approved version explains how epub accessibility testing is decided in practice, who signs it off, and what a publisher has to supply before the work can start.

Provisional paragraph. It will set out where epub accessibility testing sits in the production line, which steps depend on it, and what goes wrong downstream when it is skipped.

Provisional paragraph. The approved text names the file formats involved in epub accessibility testing, the checks each one needs, and the point at which a title is considered finished.

Provisional paragraph. Here the approved copy answers the cost question about epub accessibility testing honestly: what drives the price, what a publisher can do in-house, and what is worth buying.

Provisional paragraph. It compares the common approaches to epub accessibility testing, says which suits a small list and which suits a large one, and does not pretend the answer is the same for both.

Provisional paragraph. This is where the approved copy handles the edge cases in epub accessibility testing — tables, formulas, footnotes, illustrations — rather than leaving them to a support ticket.

Provisional paragraph. The approved version records what a publisher should ask a supplier about epub accessibility testing, and which answers should end the conversation.

Provisional paragraph. It explains how epub accessibility testing is measured, what a reasonable turnaround looks like, and how a publisher can tell a good result from a merely finished one. Provisional note 1: the approved copy will say more here about epub accessibility testing than a placeholder can. Provisional note 2: the approved copy will say more here about epub accessibility testing than a placeholder can. Provisional note 3: the approved copy will say more here about epub accessibility testing than a placeholder can. Provisional note 4: the approved copy will say more here about epub accessibility testing than a placeholder can. Provisional note 5: the approved copy will say more here about epub accessibility testing than a placeholder can. Provisional note 6: the approved copy will say more here about epub accessibility testing than a placeholder can.

Nothing on this page has been reviewed. Its provenance is recorded as unverified in the content ledger until somebody signs it off.