EPUBCheck

Official W3C conformance checker and validator for EPUB 2 and EPUB 3 publications.

1,986 Stars449 ForksJavaRelease: v5.4.0

Download Assets Official Website Documentation

Tool Overview

EPUBCheck is the official conformance checker for EPUB publications developed by the DAISY Consortium on behalf of the World Wide Web Consortium (W3C). It validates EPUB files against the official specification standards, detecting XML syntax errors, missing spine items, corrupt manifests, and accessibility issues.

System Requirements: Java Runtime Environment (JRE 11+)

Key Capabilities & Features

Official W3C reference implementation for EPUB validation

Validates EPUB 2 and EPUB 3.0/3.2/3.3 packaging and manifest structures

Detects broken internal links, missing assets, and unmanifested resources

Evaluates WCAG and EPUB Accessibility conformances

CLI tool with JSON reporting output for automated CI/CD publishing pipelines

Package Manager & CLI Installation

Install and update EPUBCheck using your preferred operating system package manager or container runtime:

$ brew install epubcheck

Verified Official Release Downloads

v5.4.0

All binaries are sourced directly from the official developer release assets without re-packaging or modifications.

Generic BinaryVerified

epubcheck-5.4.0.zip

Size: 31.56 MBDownloads: 99,641

Download Generic

Source Code ZIPVerified

epubcheck-v5.4.0-source.zip

Size: GitHub Archive

Download Source

Client-Side SHA-256 Binary Integrity Verifier

100% Client-Side. Verified locally in your browser using the Web Crypto API. No files are uploaded.

Drag & drop downloaded binary here, or browse file

Computes SHA-256 hash in real-time to guarantee file authenticity against developer releases.

Security Verification Status: Verified Official W3C Standard Tool

Downloads link directly to the official GitHub releases hosted by w3c/epubcheck. Files are checked for authentic digital developer signatures and verified against open-source repository tags.

Latest Release Changelog (v5.4.0)

![Total Downloads of EPUBCheck v5.4.0](https://img.shields.io/github/downloads/w3c/epubcheck/v5.4.0/total.svg) This is the **latest production-ready** release of EPUBCheck. It can be used to check conformance to the latest [EPUB 3.4](https://www.w3.org/TR/epub-34/) W3C Candidate Recommendation. This release was made by the DAISY Consortium for W3C. Many thanks to everyone who contributed and reported issues! EPUBCheck is also available in the Maven Central Repository as [`org.w3c:epubcheck`](https://central.sonatype.com/artifact/org.w3c/epubcheck). ### EPUB 3.4 support * **EPUB 3.4:** add 'opus' and 'aac' MP4 codecs to Core Media Types ([75f68dc](https://github.com/w3c/epubcheck/commit/75f68dce45637c56720a427737f62580eecbca25)) * **EPUB 3.4:** add AVIF and JPEG XL to Core Media Types ([5366aff](https://github.com/w3c/epubcheck/commit/5366aff34e2ca7cf19bd79e5b884ca3bbfa34ffc)), closes [#1642](https://github.com/w3c/epubcheck/issues/1642) * **EPUB 3.4:** add new message OBS_001 to report outdated features ([4ef334f](https://github.com/w3c/epubcheck/commit/4ef334f0f3d921c1e3020574f6ef255fa866bcce)) * **EPUB 3.4:** add schema validation of ITS attributes ([f2998df](ht

Specifications & Compatibility

Supported Ebook Formats

EPUBEPUB3

Supported Operating Systems

Cross-PlatformWindowsmacOSLinux

Primary LanguageJava

Software LicenseBSD-3-Clause

Official Repositoryw3c/epubcheck

Last Checked & Verified2026-11-08 04:50:07 UTC

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