Free Website Accessibility Testing Tools

Automated accessibility tools can reveal missing labels, low contrast, heading problems, and other common barriers, but no scanner can determine whether a website is fully accessible. This guide favors tools that explain findings and help a person inspect the page rather than returning a mysterious score. Use the results as a prioritized checklist, verify important issues with keyboard navigation and a screen reader, and involve people with disabilities whenever possible. Different scanners use different rules and may report different results, so a clean report from one tool is not a guarantee. The resources below work well for an initial review of a public page and for checking changes during development. They are not a substitute for understanding the Web Content Accessibility Guidelines, testing complete user journeys, or obtaining specialist help for a high-risk service. Begin with one representative page, correct repeated template problems, and then test forms, navigation, search, account flows, and error messages.

How to use this guide

These resources cover different parts of the work. Begin with the option that matches your immediate goal, then compare its guidance or results with the source material and the requirements that apply to your situation.

A practical starting point: Start with WAVE for a visual page-level review, then use Lighthouse or Accessibility Insights to compare automated findings.

External services can change their features, terms, and availability. Use the linked official destination to confirm current details, and keep your own notes or copies of important work where appropriate.

Recommended resources

WAVE

Best for: A visual first pass on an individual web page

WAVE overlays accessibility findings directly on a page and explains the rule behind each marker. That makes it useful for editors and developers who need to connect a warning to the affected content.

Keep in mind: It identifies many possible barriers, not every barrier. A person still needs to judge reading order, link purpose, keyboard behavior, and whether alternative text is meaningful.

Visit WAVE for a visual first pass on an individual web page.

Accessibility Insights for Web

Best for: Combining automated checks with a guided manual assessment

Accessibility Insights provides a quick automated check and a structured assessment workflow. Its guided steps are helpful when a team wants more than a score but is not sure what to inspect next.

Keep in mind: The extension requires a supported browser and still depends on human judgment. Completing its workflow does not certify legal compliance or prove that every user journey is accessible.

Visit Accessibility Insights for Web for combining automated checks with a guided manual assessment.

Lighthouse Accessibility Audit

Best for: Repeatable checks during web development

Lighthouse is built into Chrome DevTools and can run alongside performance and search audits. It is convenient for repeated checks while a page or component is being changed.

Keep in mind: Its accessibility score covers only tests that can be automated. A high score can coexist with serious usability problems that require keyboard, screen-reader, cognitive, and task-based testing.

Visit Lighthouse Accessibility Audit for repeatable checks during web development.

axe DevTools Browser Extension

Best for: Checking a page for common accessibility failures inside browser developer tools

The free axe extension runs automated checks in the browser and connects each result to the affected element and rule guidance.

Keep in mind: Automated checks cover only part of accessibility. The free extension does not replace keyboard, screen-reader, zoom, cognitive, or complete journey testing.

Visit axe DevTools Browser Extension for checking a page for common accessibility failures inside browser developer tools.

ARC Toolkit

Best for: Inspecting accessibility findings and page structure in Chrome developer tools

ARC Toolkit combines automated checks with panels for examining headings, landmarks, text alternatives, and other page details.

Keep in mind: It requires Chrome and knowledgeable interpretation. A page can pass its automated rules while remaining difficult or impossible for some people to use.

Visit ARC Toolkit for inspecting accessibility findings and page structure in Chrome developer tools.

IBM Equal Access Accessibility Checker

Best for: Adding open accessibility checks to development and testing workflows

IBM provides browser and development integrations built around its open accessibility rule engine, with explanations intended to support remediation.

Keep in mind: Setup varies by integration, and the rules are not a certification. Teams still need manual testing and should verify which standards and rule versions are in use.

Visit IBM Equal Access Accessibility Checker for adding open accessibility checks to development and testing workflows.

Nu Html Checker

Best for: Finding markup errors that can interfere with browsers and assistive technology

The W3C checker validates modern HTML and reports structural mistakes such as invalid nesting, duplicate identifiers, and unsupported attributes.

Keep in mind: Valid HTML is not automatically accessible, and some reported messages are technical. Use it beside accessibility testing rather than as an accessibility score.

Visit Nu Html Checker for finding markup errors that can interfere with browsers and assistive technology.

Colour Contrast Analyser

Best for: Measuring foreground and background color contrast from the screen

The Colour Contrast Analyser samples colors and compares their contrast with WCAG thresholds, including useful simulations and visual checks.

Keep in mind: A passing ratio does not prove that text is readable in context. Font size, weight, states, overlays, images, and user settings still require inspection.

Visit Colour Contrast Analyser for measuring foreground and background color contrast from the screen.

NVDA

Best for: Manually experiencing keyboard and spoken output on Windows

NVDA is a free, open-source Windows screen reader that lets teams inspect names, roles, states, reading order, forms, and dynamic announcements.

Keep in mind: Learning basic screen-reader commands takes time, and testing with NVDA alone does not represent every assistive technology or user preference.

Visit NVDA for manually experiencing keyboard and spoken output on Windows.

ANDI

Best for: Inspecting accessible names, focus order, tables, links, and page structure

ANDI is a free bookmarklet developed by the Social Security Administration that provides focused modules and element-level accessibility information.

Keep in mind: It is an inspection aid rather than a complete audit. Users need to understand its modules and confirm findings through keyboard and assistive-technology testing.

Visit ANDI for inspecting accessible names, focus order, tables, links, and page structure.