Freedom251 › Accessibility Testing Software
Ace by DAISY
What Ace by DAISY is
Ace by DAISY is a free, open-source tool for checking EPUB accessibility during publishing. It runs automated tests on EPUB content and helps evaluate conformance with the EPUB Accessibility Specification. Reports are generated in HTML and cover violations, metadata, document outlines and images. Ace can run as a command-line tool, JavaScript Node module or HTTP API, and it supports CI/CD integration, manual review tools and remediation guidance. DAISY also provides a graphical app for Windows, macOS and Linux, with Intel and some ARM installers. The desktop app can rerun evaluations, export ZIP reports and link to offline or online DAISY Knowledge Base content. Command-line use requires Node.js 20 or later, with Node.js 22 recommended. Stated systems include Windows 10+, macOS High Sierra 10.13+ and 64-bit Linux. Settings offer English and French, and documentation lists version 1.4.6.
Who it suits
Ace suits publishing teams, third-party vendors, self-publishing authors and others checking EPUB files without digital rights management. It also fits workflows needing command-line, API or desktop operation.
What it does well
- Automated EPUB accessibility tests
- HTML reports cover violations and metadata
- Command line, Node module and HTTP API
- Desktop app supports Windows, macOS and Linux
- Supports CI/CD integration and remediation guidance
What to know first
- Mobile testing is not supported
- Requires Node.js 20 or later for CLI
- DAISY has no maintenance obligation
- Latest documented version is 1.4.6
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Ace by DAISY | Free, open source EPUB accessibility checker | Free |
As daisy.org lists them, read 11 Oct 2026. The maker's own page has the final word.
Verdict
Ace offers several interfaces and report formats for EPUB accessibility evaluation. Its system requirements and stated maintenance terms should be considered before adoption.
Facts from Ace by DAISY's own pages
- Audience
- DAISY describes Ace as suitable for publishing teams, third party vendors, self publishing authors, and others testing EPUB files without digital rights management. · daisy.org, 11 Oct 2026
- Automated scans
- Yes · daisy.org, 23 Sept 2026
- Automated tests
- Ace runs automated accessibility tests on EPUB content documents. · daisy.org, 11 Oct 2026
- Browser extension
- No · daisy.org, 23 Sept 2026
- CI/CD integration
- Yes · daisy.org, 23 Sept 2026
- Current release
- The Ace documentation identifies version 1.4.6 as the latest version. · daisy.github.io, 11 Oct 2026
- Desktop app
- The official graphical app is available for Windows, macOS, and Linux, with installers for Intel and some ARM devices. · daisy.github.io, 11 Oct 2026
- Founded
- 1996 · daisy.org, 28 Sept 2026
- Free plan
- Yes · daisy.org, 23 Sept 2026
- Headquarters
- Zurich, Switzerland · daisy.org, 28 Sept 2026
- Interfaces
- Ace can be used as a command line tool, a JavaScript Node module, or through an HTTP API. · daisy.org, 11 Oct 2026
- Knowledge base
- The desktop app provides links to a local offline version of the DAISY Knowledge Base and an option to open its online version. · daisy.github.io, 11 Oct 2026
- Languages
- The desktop app settings currently offer English and French. · daisy.github.io, 11 Oct 2026
- Maintenance terms
- DAISY’s software terms say it has no obligation to provide maintenance, support, or updates for the software. · daisy.org, 11 Oct 2026
- Manual review tools
- Yes · daisy.org, 23 Sept 2026
- Mobile testing
- No · daisy.org, 23 Sept 2026
- Purpose
- Ace checks EPUB files for accessibility at any point in a publishing workflow and assists with evaluating conformance to the EPUB Accessibility Specification. · daisy.org, 11 Oct 2026
- Remediation guidance
- Yes · daisy.org, 23 Sept 2026
- Report export
- The desktop app can export a report as a ZIP archive and rerun the evaluation. · daisy.github.io, 11 Oct 2026
- Reports
- Ace generates an HTML report covering violations, metadata, document outlines, and images. · daisy.org, 11 Oct 2026
- Security and privacy
- The command line documentation says Ace requires a modern Node.js runtime for security and performance reasons. · daisy.github.io, 11 Oct 2026
- Support
- DAISY provides Ace support resources, including troubleshooting, FAQs, and contact links. · daisy.github.io, 11 Oct 2026
- Technical requirements
- The command line tool requires Node.js 20 or later, with Node.js 22 recommended; its stated operating system requirements include Windows 10+, macOS High Sierra 10.13+, and 64-bit Linux distributions. · daisy.github.io, 11 Oct 2026
- WCAG coverage
- other standard · daisy.org, 23 Sept 2026
Where Ace by DAISY stands on Freedom251
- Accessibility Testing Software#50 of 169