WCAG 2.0 vs. 2.1: What’s the Difference?

The best practices of digital accessibility evolve with the latest trends in technology and user behavior — and so do the accessibility standards that govern it.

While the Web Content Accessibility Guidelines (WCAG) 2.0 laid the foundation for modern digital accessibility, WCAG 2.1 was introduced to close important gaps, especially around mobile and cognitive accessibility.

If you’re comparing WCAG 2.0 vs 2.1, you’re likely familiar with the basics of WCAG. Instead of rehashing those, we’ll focus on the difference between the two: what changed, why it changed, and which version matters today.

Why WCAG Was Updated After 2.0

WCAG 2.0 was released in 2008, before smartphones and tablets became the default way people interacted with digital content. As mobile usage grew — along with a better understanding of how people with disabilities interacted with touch-first interfaces — limitations in WCAG 2.0 became clear.

WCAG 2.1 was published in 2018 to address those gaps. Instead of replacing WCAG 2.0, WCAG 2.1 updates and extends it, adding new success criteria focused on how people actually interact with digital content.

A stylized web browser surrounded by icons for hearing disabilities, visual disabilities, motor disabilities, and cognitive disabilities.

Key Differences Between WCAG 2.0 and 2.1

At its core, WCAG 2.1 keeps everything from WCAG 2.0 and adds 17 new success criteria. The difference isn’t about rethinking accessibility standards, but addressing gaps that became clear as technology and user behavior evolved.

In short:

• WCAG 2.0 established the core accessibility framework.

• WCAG 2.1 builds on that framework to improve usability for mobile users, people with low vision, and people with cognitive or motor disabilities.

New Accessibility Areas Addressed in WCAG 2.1

Rather than listing all 17 new criteria individually, WCAG 2.1 is best understood by the three problems it set out to address:

Mobile & Touch Accessibility

WCAG 2.1 improves how content works on touchscreens and mobile devices. New requirements address:

• Complex gestures that require multiple fingers

• Accidental taps or motion-based actions

• Switching between input methods (touch, keyboard, voice)

These changes reflect how users interact with modern devices — not just desktops.

Low Vision Support

WCAG 2.1 expands accessibility for users who rely on zoom, magnification, or visual customization. Updates focus on:

• Reflowing content without horizontal scrolling

• Adequate contrast for non-text elements like buttons and icons

• Adjustable text spacing without breaking layouts

Cognitive Accessibility

Several new criteria support users who benefit from clarity, predictability, and reduced cognitive load. These updates help ensure:

• Inputs and controls are clearly identified

• Time limits don’t create unnecessary barriers

• Motion and animation don’t cause distraction or disorientation

• Status messages are announced clearly by assistive technologies

Accessibility symbol surrounded by icons with accessibility issues listed under them.

Does WCAG 2.1 Replace WCAG 2.0?

No. WCAG 2.1 does not replace or invalidate WCAG 2.0.

Instead, WCAG 2.1 includes every success criterion from WCAG 2.0, plus additional requirements. If a website meets WCAG 2.1, it also meets WCAG 2.0 by default.

Learn more about WCAG compliance

Which Version Should Websites Follow Today?

Today, WCAG 2.1 Level AA is widely treated as the most relevant accessibility benchmark. It reflects current technology, modern usage patterns, and how people with disabilities actually experience digital content.

While some accessibility laws still reference WCAG 2.0, enforcement expectations increasingly align with WCAG 2.1 — especially for mobile experiences. By designing and testing against WCAG

Learn how AudioEye helps organizations maintain WCAG compliance as accessibility standards evolve