Free Accessibility Testing Directly in VS Code with axe DevTools

The axe DevTools extension for VS Code is completely free and checks your code for accessibility issues while you develop. No license costs, no hidden fees – just instant feedback on accessibility issues.

Why Free Tools Provide Enormous Value

Early feedback helps you correct the affected component before reusing the same mistake across more pages.

Research demonstrates ¹ that teams with accessibility tools save 2,000 development hours in 6 months. Issues are fixed "in less than one hour on average" – when found early.

The Market is Waiting:

• 1 billion people globally have disabilities ²
• Accessible websites show 28% higher revenue ³
• The European Accessibility Act is in effect since June 2025

How the Free Extension Works

The free Axe Accessibility Linter for VS Code checks source files against supported rules, such as missing labels or invalid ARIA. Deque’s rule list describes what it checks.

Check text contrast on the rendered page with a browser-based testing tool. Test keyboard and screen reader interactions manually as well.

Live Example While You Type:

function ShopButton() {
  return (
    <button>
      <img src="cart.svg" />  
      {/* ⚠️ Extension shows immediately: "Image needs alt text" */}
    </button>
  );
}

The extension underlines issues in red – just like spell check. Hover over it and you see:

• What the problem is
• How to fix it

Installation in 30 Seconds

1. Open VS Code
2. Go to Extensions (Ctrl+Shift+X)
3. Search "axe Accessibility Linter"
4. Click Install

That's it! The extension runs immediately and automatically checks all HTML, React, Vue, and Angular files.

Getting Started Without Configuration

After installation, everything works out-of-the-box:

• ✅ Automatic checking of all web files
• ✅ Instant feedback while you type
• ✅ Zero false positives – only real issues

Example of Issue Detection:

// Problem detected and marked with red underline
<img src="logo.png" />
// ⚠️ Hover tooltip shows: "Images must have alternate text"

// Fix based on tooltip guidance
<img src="logo.png" alt="Company logo" />

Optional Customization for Your Team

If you want to adjust rules, create an axe-linter.yml file in your project folder:

rules:
  # Example: Disable html-has-lang rule
  html-has-lang: false
  
  # Example: Enable image-alt rule
  image-alt: true
  
  # Example: Enable button-name rule
  button-name: true
  
# Optional: Exclude certain files
exclude:
  - "*.tmp"
  - "test/**/*"

Configuration Options:

• true – Rule enabled
• false – Rule disabled
• The extension automatically searches for axe-linter.yml in your project directory
• Find all available rules here

Practical Examples of Common Issues

1. Missing Button Text

// ❌ Problem: Screen reader can't describe button
<button><IconSave /></button>

// ✅ Solution: Add label
<button aria-label="Save"><IconSave /></button>

2. Missing Language Declaration

<!-- ❌ Problem: HTML without language attribute -->
<html>
  <head><title>My Website</title></head>
  <body>Content</body>
</html>

<!-- ✅ Solution: Add lang attribute -->
<html lang="en">
  <head><title>My Website</title></head>
  <body>Content</body>
</html>

3. Images Without Alt Text

<!-- ❌ Problem: Screen reader skips image -->
<img src="team.jpg">

<!-- ✅ Solution: Add description -->
<img src="team.jpg" alt="Our development team">

Team Integration

For Individual Developers:

• Just install and start
• Learn through direct feedback
• No training needed

For Teams:

• Share settings via GitHub
• Define common rules
• Establish consistent accessibility standards

ROI of a Free Extension

What You Save:

• 0€ license costs (vs. thousands for enterprise tools)
• 75% lower fix costs than in QA/production ⁴
• Hours of manual testing

Time Investment:

• Installation: 30 seconds
• First use: Immediate
• Learning curve: Learning by doing

Why Free is So Valuable

The axe DevTools extension is based on axe-core, the world's most-used open-source accessibility engine. Over 1 billion downloads ⁷ and used by Google, Microsoft, and other tech giants.

No More Excuses:

• ❌ "Accessibility tools are too expensive"
• ❌ "We have no budget for testing"
• ❌ "Training takes too long"

With a free, immediately usable extension, there's no reason to neglect accessibility anymore.

Conclusion: Start Free, Today

The axe DevTools extension makes accessibility testing as easy as spell checking. Free, immediately usable, no training required. Every bug saved pays off multiple times.

Your Next 3 Minutes:

1. Install extension (30 sec)
2. Open a file (30 sec)
3. Fix first issues (2 min)

The EAA is in effect. A free extension that prevents problems before they become expensive – what's there to lose?