Tools

Accessibility Insights

Also: AI for Web, Accessibility Insights for Web, Accessibility Insights for Windows

Microsoft's free open-source accessibility testing tool — both an automated checker (axe-core under the hood) and a guided manual-test framework that walks auditors through structured assessments.

Accessibility Insights is Microsoft’s family of free, open-source accessibility testing tools. It’s built on top of axe-core but adds something the raw axe-core ecosystem doesn’t provide: a structured, guided manual-test framework that walks a human auditor through every WCAG criterion that automation cannot check.

The three products

  1. Accessibility Insights for Web — a browser extension (Chrome / Edge / Edge Dev) that runs against web pages.
  2. Accessibility Insights for Windows — a desktop application for testing native Windows apps.
  3. Accessibility Insights for Android — a mobile testing companion for native Android apps.

The web version is by far the most-used and is the focus here.

What it does that axe-core alone doesn’t

axe-core gives you a list of automated findings. Accessibility Insights gives you that plus two more modes:

  1. FastPass — a 5-minute automated + lightly-guided test that combines axe-core automated checks with two quick manual checks (tab stops verification and a brief landmarks check). Designed for developers who want to sanity-check before merging a PR.

  2. Assessment — a comprehensive guided manual test covering roughly 30 WCAG criteria that can’t be automated. The user walks through each section, with on-screen instructions describing how to test (e.g., “Tab through the entire page. Does focus order match visual order?”), the criterion text, examples of pass / fail, and a place to record results. The end output is a structured pass/fail report against every applicable criterion.

The Assessment workflow is the major differentiator. It’s the most accessible introduction to real accessibility auditing — the kind that goes beyond automated checks into focus order, screen-reader behaviour, contrast judgment in context, and form-error handling.

Why this matters

Most accessibility-audit failure cases are people who relied on automated tools for everything and discovered too late that ~60-70% of WCAG issues need human judgment. Accessibility Insights bridges that gap: the same tool that runs your automated checks also walks you through the manual ones, with criterion-by-criterion guidance.

How to use it operationally

Three integration patterns:

  • Developer self-test before PR. Run FastPass on changed pages, catch the easy issues, hand off cleaner code to manual review.
  • QA-level assessment for major releases. Run the full Assessment workflow against critical user flows. The output is a proper WCAG-criteria pass/fail record.
  • External-audit preparation. Run the full Assessment in-house before bringing in an external auditor. The auditor finds fewer surprises; your team has a better understanding of the issues.

Limitations

Accessibility Insights is excellent for structured guided testing. It is not:

  • A continuous integration tool. axe-core / Pa11y are the right CI choices.
  • A real-user replacement. Disabled-user usability sessions still find things the automated + guided framework misses.
  • A substitute for testing with actual assistive technology. Accessibility Insights helps you ask the right questions about screen-reader behaviour, but you still need to fire up NVDA or VoiceOver and confirm.

The combined practice — Accessibility Insights for manual audit, axe- core for CI, real screen readers for spot validation — covers more ground than any single tool.