axe-core in VitalSite
How VitalSite uses axe-core — the industry-standard, open-source accessibility engine by Deque Systems — to test your domain against WCAG 2.1.
axe-core is the most widely used accessibility testing engine in the world. Built and maintained by Deque Systems and released under the open-source MIT license, it powers the accessibility tooling in Chrome DevTools, Lighthouse, and countless professional auditing products. VitalSite runs axe-core against every page it crawls so your accessibility check uses the same engine the experts trust.
What it provides
axe-core evaluates a fully rendered page against the Web Content Accessibility Guidelines (WCAG) 2.1 — the standard referenced in the ADA website-accessibility lawsuits that have surged in recent years. It detects issues across colour contrast, image alt text, form labels, ARIA usage, heading structure, keyboard operability, and more, with an extremely low false-positive rate.
Why we use it
Accessibility is no longer optional — it’s a legal, ethical, and commercial requirement. Rather than reinvent a rules engine, VitalSite uses the open-source standard so results are credible, reproducible, and aligned with what an accessibility consultant would find. VitalSite organises axe-core’s output into 16 plain-English categories, each mapped to its exact WCAG 2.1 success criterion.
How VitalSite uses it
During the same unified crawl that powers the security scan, VitalSite renders each page in a real browser, injects axe-core, and runs it against WCAG 2.1 A, AA, and AAA rules. Findings are scored (Level A failures are most severe), paired with a code-level fix and a verification step, and shown in the Accessibility tab alongside your security and visibility results — one scan, three pillars.
Every VitalSite scan draws on this source automatically. Run a free full-domain scan to see your results, or compare plans and pricing.
See if this affects your site
Run a free full-domain scan — this check runs on every page, with an exact fix guide.