EPUBCheck · Ace by DAISY

Validate your EPUB before you send it to the store.

The official W3C validator and DAISY's accessibility checks, with every problem explained.

The file is validated in the European Union and deleted when the checks finish; the report, within 24 hours at most. See a sample report

How to read the report

Three answers, not one.

  1. 01

    Format validity

    EPUBCheck checks the file against the W3C EPUB specification. Only this part decides whether the EPUB is valid.

  2. 02

    Accessibility software can check

    Ace by DAISY opens every document in the book and finds what a machine can find: images with no alternative text, documents with no language, missing metadata. Each finding cites its WCAG criterion and its clause in the European standard EN 301 549.

  3. 03

    Accessibility that needs human judgement

    An image having alternative text does not mean the text describes it. The report tells you what is left to review; deciding it is a person's job.

For one file, this is enough. For a catalogue, let's talk.

The same checks run inside Lantia's platform on every title before every delivery to a store.

Talk to the digital distribution team