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Pa11y

pa11y.org

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Spec score 8.7 #14 of 133 in Website Accessibility Tools

What it is

Pa11y is a free, open-source set of tools for checking website accessibility. Its command-line interface loads a page for a one-off test and highlights issues, while Pa11y CI checks a list of pages in continuous-integration workflows. Pa11y Dashboard tests pages daily and graphs improvements or regressions over time. Pa11y Webservice supplies JSON data for the Dashboard or a custom dashboard-style front end. The package runs from the command line or Node.js, uses HTML_CodeSniffer by default, and can also use the axe test runner. WCAG2AA is the default CLI standard, with WCAG2A and WCAG2AAA selectable. Reports can be human-readable CLI output, CSV, HTML, JSON, or TSV. Configuration uses command-line options or JSON and JavaScript files, and local HTML files can be tested with an absolute path. Pa11y provides API access, scheduled scans, site-level scanning, and CI/CD integration across Linux, macOS, Windows, web, API, and self-hosted setups. Pa11y 10 requires Node.js 22.13.0 or newer on an even-numbered release.

Spec sheet

Purpose
Pa11y publishes free, open-source tools to help designers and developers make web pages more accessible.Read 10 Oct 2026 · pa11y.org
Free plan
YesRead 21 Sep 2026 · pa11y.org
License
The Pa11y repository lists the LGPL-3.0 license.Read 10 Oct 2026 · github.com
API access
YesRead 21 Sep 2026 · pa11y.org
CI testing
Pa11y CI iterates over a list of web pages and highlights accessibility issues, with a focus on continuous integration.Read 10 Oct 2026 · pa11y.org
CI/CD integration
YesRead 21 Sep 2026 · pa11y.org
CLI and Node.js
The Pa11y package runs accessibility tests from the command line or Node.js.Read 10 Oct 2026 · github.com
CLI testing
The Pa11y command-line interface loads a web page and highlights accessibility issues for one-off tests.Read 10 Oct 2026 · pa11y.org
Configuration
Pa11y supports configuration through command-line options and JSON or JavaScript configuration files.Read 10 Oct 2026 · github.com
Dashboard
Pa11y Dashboard automatically tests web pages daily and graphs improvements and regressions over time.Read 10 Oct 2026 · pa11y.org
Local file testing
Pa11y can test a local HTML file when given an absolute path.Read 10 Oct 2026 · github.com
Operating systems
The project documents installation requirements for Linux, macOS, and Windows 11.Read 10 Oct 2026 · github.com
Reports
Built-in CLI reporters include human-readable CLI output, CSV, HTML, JSON, and TSV.Read 10 Oct 2026 · github.com
Runtime requirement
Pa11y 10 requires Node.js 22.13.0 or above, using an even-numbered Node.js version.Read 10 Oct 2026 · github.com
Scan scope
siteRead 21 Sep 2026 · pa11y.org
Scheduled scans
YesRead 21 Sep 2026 · pa11y.org
Standards
The CLI offers WCAG2AA by default and also lists WCAG2A and WCAG2AAA as selectable standards.Read 10 Oct 2026 · github.com
Test runners
Pa11y supports HTML_CodeSniffer by default and also supports the axe test runner.Read 10 Oct 2026 · github.com
WCAG version
wcag 2.1Read 21 Sep 2026 · pa11y.org
Webservice
Pa11y Webservice is a JSON-based service that backs Pa11y Dashboard and can supply data to a custom dashboard-like front end.Read 10 Oct 2026 · pa11y.org

Plans and prices

Pa11y open-source tools Free Free and open source tools Read 10 Oct 2026 · pa11y.org

Every Pa11y plan and price →

Strong points and limits

Strong points

  • Free and open-source tools
  • Daily Dashboard scans with trend graphs
  • CI/CD integration and API access
  • Multiple report formats
  • Selectable WCAG2A, WCAG2AA, and WCAG2AAA standards

Limits

  • Pa11y 10 requires Node.js 22.13.0 or newer
  • Installation requirements include an even-numbered Node.js version

Who it suits

Pa11y suits designers and developers who need accessibility checks for websites, individual pages, local files, or continuous-integration workflows.

Verdict

Pa11y combines one-off, scheduled, dashboard, and CI accessibility checks in one toolkit. Its standards, outputs, configuration methods, and deployment options are clearly specified.

Where Specifiction places it

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