Accessibility Tools

Building an accessible website is not a one-time task — it is an ongoing commitment that requires the right set of tools at every stage of development. Automated accessibility testing tools can catch roughly 30–50% of WCAG violations programmatically, covering issues like missing alt text, insufficient color contrast, broken ARIA attributes, and missing form labels. The remaining issues require manual testing with screen readers and keyboard navigation. This lesson covers the most important tools in both categories, explains their strengths and limitations, and helps you choose the right combination for your workflow.

CodeFrog

Pricing: $99/year — Platform: Desktop app (Mac and Windows)

CodeFrog is a desktop application that runs comprehensive quality audits on any website, including sites running on localhost. Its accessibility scanning is powered by the axe-core engine, the same engine used by axe DevTools and many other industry-standard tools. What sets CodeFrog apart is its ability to test local development servers before you deploy, catching accessibility issues at the earliest possible stage.

CodeFrog generates a detailed mega report that includes accessibility findings alongside security, performance, SEO, and code quality results. Each finding includes the specific WCAG criterion violated, the severity level, the affected HTML element, and actionable remediation guidance. Because the accessibility scan runs as part of a broader quality audit, you get a holistic view of your site's health in a single report.

Best use cases

• Testing localhost and staging environments before deployment
• Running comprehensive quality audits that include accessibility as one dimension
• Teams that want a single tool covering multiple quality areas
• Developers who prefer a desktop app over browser extensions

axe DevTools

Pricing: Free browser extension; paid Pro version with guided manual testing — Platform: Chrome, Firefox, Edge extensions

axe DevTools by Deque Systems is the most widely used accessibility testing browser extension. It integrates directly into Chrome DevTools and uses the axe-core engine to scan the current page for WCAG 2.1 Level A and AA violations. The free version provides automated scanning with clear issue descriptions, impact ratings, and fix suggestions.

The paid Pro version adds guided manual testing workflows — it walks you through keyboard navigation checks, screen reader testing, and other manual tests that automated tools cannot perform. This is valuable because automated testing alone misses over half of all accessibility issues.

Best use cases

• Quick, on-the-fly accessibility checks during development
• Debugging specific accessibility issues in the browser
• Teams that need guided manual testing workflows (Pro)
• Integration with Deque's accessibility management platform (Enterprise)

Pa11y

Pricing: Free, open-source — Platform: Node.js CLI, CI/CD integration

Pa11y is a free, open-source accessibility testing tool designed for automated pipelines. It runs from the command line or as a Node.js library, making it ideal for CI/CD integration. Pa11y can test against WCAG 2.1 Level A, AA, or AAA standards, and it supports multiple testing runners including axe-core and HTML CodeSniffer.

Pa11y Dashboard provides a web interface for monitoring accessibility across multiple URLs over time, and Pa11y CI is specifically designed for continuous integration, allowing you to fail builds when accessibility regressions are introduced. This makes Pa11y one of the best options for teams that want to enforce accessibility standards automatically.

Best use cases

• CI/CD pipeline integration to catch accessibility regressions
• Automated testing of multiple pages in batch
• Teams that need a free, self-hosted accessibility monitoring solution
• Projects that want to fail builds on accessibility violations

WAVE

Pricing: Free browser extension; paid API access — Platform: Chrome and Firefox extensions, web service

WAVE (Web Accessibility Evaluation Tool) is developed by WebAIM, one of the most respected accessibility organizations. Unlike other tools that list issues in a panel, WAVE uses a visual overlay approach — it injects icons and indicators directly into your page to show exactly where issues, alerts, and structural elements are located.

This visual approach makes WAVE particularly effective for understanding the spatial context of accessibility issues. You can immediately see which image is missing alt text, which heading breaks the hierarchy, or which form field lacks a label. WAVE also identifies structural elements like headings, landmarks, and ARIA attributes, giving you a visual map of your page's accessibility architecture.

Best use cases

• Visual learners who benefit from seeing issues in context on the page
• Quick accessibility assessments of live pages
• Checking heading hierarchy and document structure visually
• Identifying color contrast issues with the built-in contrast checker

Lighthouse

Pricing: Free, built into Chrome — Platform: Chrome DevTools, CLI, Node.js module

Lighthouse is Google's open-source tool for auditing web page quality. Its accessibility audit uses a subset of axe-core rules to check for common WCAG violations. While Lighthouse's accessibility coverage is not as comprehensive as dedicated tools like axe DevTools or Pa11y, its convenience is unmatched — it is built directly into Chrome DevTools and produces a scored report covering accessibility, performance, SEO, and best practices in a single run.

Lighthouse provides an accessibility score from 0 to 100 based on the issues found. Each issue includes a description, the affected elements, and a link to the relevant documentation. The score is useful as a quick health check, but it should not be treated as a comprehensive accessibility assessment.

Best use cases

• Quick accessibility health check without installing any extensions
• Broad quality audits covering accessibility alongside performance and SEO
• CI/CD integration via the Lighthouse CLI or lighthouse-ci package
• Generating shareable reports for stakeholders

Screen Readers

Automated tools cannot fully replace manual testing with screen readers. Screen readers are assistive technology that reads web content aloud and allows keyboard-only navigation. Testing with screen readers reveals issues that no automated tool can detect, such as confusing reading order, missing context, unclear link text, and poor ARIA usage.

VoiceOver (Free, macOS and iOS)

VoiceOver is Apple's built-in screen reader, available on every Mac and iOS device at no extra cost. On macOS, activate it with Cmd + F5. VoiceOver is well-integrated with Safari, making it the best choice for testing on Apple platforms. Learning the rotor (Ctrl + Option + U) is essential — it provides a quick way to navigate by headings, links, landmarks, and form controls.

NVDA (Free, Windows)

NVDA (NonVisual Desktop Access) is a free, open-source screen reader for Windows. It is the second most popular screen reader globally and works best with Firefox. NVDA is maintained by NV Access, a non-profit organization, and is funded entirely by donations. For testing accessibility on Windows, NVDA paired with Firefox gives you the most standards-compliant combination.

JAWS (Paid, Windows)

JAWS (Job Access With Speech) is the most widely used commercial screen reader, particularly in enterprise environments. It provides the most comprehensive screen reader experience on Windows and is the primary screen reader used by many blind and visually impaired professionals. JAWS works best with Chrome and Internet Explorer. A personal license costs approximately $1,000, with annual maintenance fees for updates.

When to use screen readers

• After automated testing to catch the issues that tools miss
• Testing dynamic content, modals, and single-page application navigation
• Verifying that ARIA live regions announce updates correctly
• Checking the reading order and focus management of complex interfaces

Color Contrast Tools

WebAIM Contrast Checker

Pricing: Free — Platform: Web

WebAIM Contrast Checker is a simple, reliable tool for checking color contrast ratios against WCAG 2.1 requirements. Enter foreground and background colors in hex, and it instantly shows the contrast ratio and whether it passes AA and AAA standards for normal and large text. It is the quickest way to verify that your color choices meet accessibility requirements.

Stark (Figma Plugin)

Pricing: Free tier; paid Pro version — Platform: Figma, Sketch, Adobe XD

Stark is a design plugin that integrates accessibility checking directly into your design workflow. It provides contrast checking, color blindness simulation, and focus order annotation within Figma, Sketch, and Adobe XD. Stark shifts accessibility left into the design phase, catching color contrast issues before any code is written.

Training and Education

Deque University

Pricing: Paid individual and enterprise plans — Platform: Web-based courses

Deque University is the most comprehensive online training platform for web accessibility. Courses cover WCAG, ARIA, accessible design patterns, screen reader testing, and accessibility management. The curriculum is developed by Deque Systems, the same organization behind axe-core, and is used by many organizations for accessibility training and certification preparation.