What Is WCAG 2.1? A Plain-Language Guide for WordPress Site Owners

What does WCAG stand for?

WCAG stands for Web Content Accessibility Guidelines. Published by the World Wide Web Consortium (W3C), these guidelines define how to make web content accessible to people with disabilities — including visual, auditory, motor, and cognitive impairments.

The current standard is WCAG 2.1, released in 2018, with Level AA as the most commonly required conformance level.

Why should WordPress site owners care?

Two reasons: legal risk and better user experience.

Legal risk is real

The European Accessibility Act (EAA) came into effect in June 2025, requiring websites serving EU customers to meet WCAG 2.1 AA. Fines can reach €500,000.
In the United States, the ADA has been increasingly applied to websites. Over 4,000 web accessibility lawsuits were filed in 2024 alone, with average settlements exceeding $25,000.
Canada’s AODA has required WCAG compliance for large organizations since 2021.

Better UX for everyone

Accessibility improvements benefit all users, not just those with disabilities. Proper heading structure helps SEO. Alt text helps when images fail to load. Keyboard navigation helps power users. Clear form labels reduce errors for everyone.

The four principles of WCAG

WCAG is organized around four principles, known as POUR:

Perceivable — Information must be presentable in ways users can perceive. This includes alt text for images, captions for video, and sufficient color contrast.
Operable — Users must be able to operate the interface. This means keyboard navigation, no time limits that can’t be extended, and no content that causes seizures.
Understandable — Content and interface must be understandable. This includes readable text, predictable navigation, and helpful error messages.
Robust — Content must work with current and future technologies, including screen readers and other assistive tools.

What does Level AA require?

WCAG defines three conformance levels:

Level A — The bare minimum. Addresses the most severe barriers.
Level AA — The standard most laws reference. Covers the most common accessibility issues.
Level AAA — The highest level. Not typically required by law due to its strictness.

Most legal requirements target Level AA, which includes criteria like:

All images have meaningful alt text (or are marked as decorative)
Color contrast of at least 4.5:1 for normal text
All form fields have visible labels
Headings follow a logical hierarchy
The page language is specified
Content is navigable by keyboard alone

How WP Comply helps

WP Comply scans your entire WordPress site for WCAG 2.1 Level AA violations. The free version identifies every issue and gives you a Compliance Score from 0 to 100.

The Pro version goes further — using AI to auto-generate alt text, fix heading hierarchies, add form labels, and apply skip links. All fixes happen in your actual source code, not through a JavaScript overlay.

Install WP Comply free →

This post is part of our series on web accessibility. Next: European Accessibility Act Compliance Guide.