Web accessibility means designing and developing websites that people with disabilities can use. This includes people with visual, auditory, motor, and cognitive disabilities, approximately 15% of the world's population.
Why Accessibility Matters
It's the right thing to do
Everyone deserves equal access to information and functionality.
It's often legally required
The ADA, Section 508, and laws in many countries require accessible websites. Lawsuits against inaccessible websites are increasing.
It helps everyone
Curb cuts help wheelchair users but also people with strollers, delivery workers, and cyclists. Similarly, accessible design benefits all users:
- Captions help non-native speakers
- Clear navigation helps everyone
- Good contrast helps in bright sunlight
It's good for SEO
Accessible sites are well-structured, which search engines prefer.
WCAG Guidelines
The Web Content Accessibility Guidelines (WCAG) are the international standard. They're organized around four principles, called POUR:
Perceivable
Users must be able to perceive the content:
- Text alternatives for images (alt text)
- Captions for videos
- Sufficient color contrast
- Content adaptable to different presentations
Operable
Users must be able to operate the interface:
- Keyboard accessibility (no mouse required)
- Enough time to read and interact
- No content that causes seizures
- Clear navigation and wayfinding
Understandable
Users must be able to understand the content:
- Readable and predictable
- Input assistance (error prevention and recovery)
- Consistent navigation and identification
Robust
Content must work with current and future technologies:
- Valid, semantic HTML
- Works with assistive technologies
- Graceful degradation
Common Accessibility Issues
- Images without alt text
- Poor color contrast
- Keyboard traps (can't tab out of elements)
- Missing form labels
- Auto-playing media
- Non-descriptive link text ("click here")
Testing Accessibility
- Automated tools: axe, WAVE, Lighthouse
- Manual testing: Keyboard navigation, screen readers
- User testing: With people who use assistive technologies