If you've ever wondered why some websites feel impossible to navigate without a mouse, or why certain color combinations make text unreadable, you've encountered accessibility issues that WCAG aims to solve.
The Web Content Accessibility Guidelines (WCAG) 2.1 is the international standard for web accessibility, published by the World Wide Web Consortium (W3C). These guidelines provide a framework for making web content accessible to people with disabilities, including visual, auditory, motor, and cognitive impairments.
The Four Principles of WCAG (POUR)
WCAG is organized around four fundamental principles, remembered by the acronym POUR:
1. Perceivable
Information must be presentable to users in ways they can perceive. This means providing text alternatives for images, captions for videos, and ensuring content can be presented in different ways without losing meaning.
2. Operable
Users must be able to operate the interface. All functionality should be available via keyboard, users should have enough time to read content, and navigation should be predictable and consistent.
3. Understandable
Information and operation of the interface must be understandable. Text should be readable, web pages should appear and operate in predictable ways, and users should be helped to avoid and correct mistakes.
4. Robust
Content must be robust enough to be interpreted by a wide variety of user agents, including assistive technologies. This means using valid, semantic HTML and following web standards.
Conformance Levels: A, AA, and AAA
WCAG defines three levels of conformance:
- Level A: The minimum level. Sites must meet these criteria or some users will be completely unable to access content.
- Level AA: The recommended target for most websites. This is what most accessibility laws reference.
- Level AAA: The highest level. While aspirational, it's not always possible to meet all AAA criteria for all content.
What's New in WCAG 2.1?
WCAG 2.1, released in 2018, added 17 new success criteria to address:
- Mobile accessibility: Touch targets, orientation, and input methods
- Low vision: Text spacing, reflow, and contrast for non-text elements
- Cognitive disabilities: Timeouts, animation controls, and consistent navigation
Getting Started with Compliance
The best approach is to start with Level AA compliance. Focus on:
- Adding alt text to all meaningful images
- Ensuring keyboard navigation works throughout your site
- Meeting color contrast requirements (4.5:1 for normal text)
- Using proper heading hierarchy
- Adding form labels and error messages
Tools like SiteDNA can automatically scan your website and identify WCAG violations, giving you a prioritized list of issues to fix. This makes the journey to compliance much more manageable.
Why WCAG Matters
Beyond legal compliance, accessible websites reach more users, perform better in search engines, and provide a better experience for everyone. An estimated 15% of the world's population lives with some form of disability—that's over a billion potential users.
Start your accessibility journey today. Run a free scan with SiteDNA to see where your website stands.