Sa11y the accessibility quality
assurance assistant

Made for content

Illustration of a gauge pointing to a content author instead of a web developer.

Sa11y visually highlights content issues at the source with a simple tooltip on how to fix them.

Sa11y is not a comprehensive code analysis tool, nor is it a web accessibility overlay.


Developers and a11y experts

Sa11y is a customizable, framework-agnostic JavaScript plugin.

Over six hundred thousand requests a month on jsDelivr.

  • Over 50 checks that encourage quality accessibility.
  • Automatic: checks content on page load.
  • Customizable: Dozens of props to fine tune the experience for content authors.
  • Focus on the issues: Turn off irrelevant checks and add exclusions.
  • Scalable: Check every page for accessibility.
  • Shadow DOM support: Ability to check inside web components or elements with an open Shadow DOM.

Developer docs

Open source

Sa11y is 100% free and open source. You can view the source code on GitHub. Sa11y was made open source in 2020 to help content authors around the world create accessible content for people with disabilities.

Sa11y was originally developed as a custom accessibility checker for Toronto Metropolitan University 's content management system and its several hundred content authors.


No personal data is ever collected when you use Sa11y. No tracking, no analytics, no third party content. Sa11y only uses your browser’s web storage to remember the state of optional rulesets and other features you enable.

Only this website uses privacy-oriented analytics. The analytics do not track IP addresses, fingerprints or cookies.

Featured on

Stanford University's Office of Digital Accessibility, Browser Plugins page.
Queen's University: WebPublish Service and Support accessibility resources page.
Princeton University. Introducing Editoria11y: Accessibility Autocorrect page.
Featured on the University of Toronto's blog post: Bringing Awareness to Accessibility.
Vancouver Island University's Facebook post mentioning Sa11y.
Laurentian University's web accessibility resources page.
University of Arizona's browser plugins section.
Santa Clara University's support page on using Sa11y.
Civic Actions' Accessibility Playbook tools page.
Joomla's 4.1 release note mentions accessibility checker powered by Sa11y.
University of Winsconsin-Madison's Digital Accessibility Policy page features Sa11y.
The A11y Project's resources page.
MERLOT: Multimedia Educational Resource for Learning and Online Teaching.
Implemented within San Diego State University's content management system.
Turnkey plugin available in REDAXO CMS.
Featured on Hubspot Blog.
Available to LibPress site managers within the BCLibraries Cooperative.