WCAG explains what makes websites, apps, and other digital properties accessible to people with disabilities. While WCAG itself isn’t a law, it’s the accepted global benchmark for web accessibility, and has been incorporated into laws and regulations around the world.
Key insights
What is WCAG?
WCAG is widely acknowledged as the global standard for website accessibility. These guidelines offer a clear, technical, and measurable framework for designing websites, digital content, and digital applications that are accessible to users with a wide range of disabilities. They set out testable success criteria for web pages and other digital content, including how that content works with user agents such as browsers and assistive technologies.
WCAG is developed within the W3C Web Accessibility Initiative (WAI) by the Accessibility Guidelines Working Group, a multi-stakeholder group of accessibility experts, regulators, academics, and businesses from around the world.
What are the four principles of WCAG?
Four principles, often referred to as “POUR,” guide WCAG.
Perceivable
Information and user interface components must be presented in ways that users can sense. This means providing users with options for perceiving content in different ways, for example, by adjusting color contrast, resizing text, or accessing captions for videos.
Operable
Users must be able to interact with and navigate the user interface in ways that suit their needs. For example, all functions should be accessible via keyboard, voice commands, or other input methods, not just a mouse.
Understandable
The content and operation of the user interface must be easy to comprehend. Instructions should be clear, and navigation should be intuitive, allowing users to understand and interact with the site without confusion.
Robust
Content should be robust enough that a broad range of users and assistive technologies can interpret it. As technology evolves, the site should remain accessible and functional for users of relevant assistive tools. As the W3C puts it, organizations should "maximize compatibility with current and future user agents."
What are the WCAG conformance levels?
There are three levels of WCAG conformance: A, AA, and AAA.
Each level builds on the one before it. So, to reach Level AA, you must first meet all Level A requirements, and to reach Level AAA, you must also satisfy all Level AA success criteria.
This is the basic level of accessibility, covering essential considerations for a broad range of users. However, some barriers may still remain for certain groups.
This is the level that most organizations aim for, and that is commonly included in regulations or legal agreements. It offers broader access than Level A, especially for users of assistive technologies.
This is the highest level of conformance. It provides accessibility for the widest range of users but isn’t always practical or necessary in every situation. Some organizations aim to meet specific Level AAA criteria, while using Level AA as a baseline.
Which version of WCAG should you use?
WCAG is updated to keep pace with changing technology. Four versions have been published as W3C Recommendations, and WCAG 3.0 is in development.
| Version | Status | Published | What it added |
|---|---|---|---|
| WCAG 1.0 | Superseded and no longer recommended | The first version of the guidelines | |
| WCAG 2.0 | W3C Recommendation | Technology-agnostic success criteria organized under the four POUR principles | |
| WCAG 2.1 | W3C Recommendation | 17 new success criteria covering low vision, cognitive and learning disabilities, and mobile devices | |
| WCAG 2.2 | Current W3C Recommendation | (updated ) | 9 new success criteria improving access for people with low vision, cognitive disabilities, and motor disabilities; removed 4.1.1 Parsing |
| WCAG 3.0 | W3C Working Draft, not yet a standard | Latest draft | A proposed new structure and conformance model; no release date set |
WCAG 2 versions are backwards compatible. Content that conforms to WCAG 2.2 also conforms to WCAG 2.1 and WCAG 2.0. The W3C recommends using the most recent version, and Level AA conformance with WCAG 2.2 keeps your site aligned with evolving best practices.
For more information about each update, reference our guide to WCAG 2.1 success criteria, our WCAG 2.2 checklist, and the W3C’s summary of what’s new in WCAG 2.2.
What about WCAG 3.0?
The W3C Accessibility Guidelines (WCAG) 3.0 are a Working Draft that proposes a broader scope and a new way of measuring conformance. The draft will continue to change before it becomes a standard. Until then, WCAG 2.2 remains the current standard, and laws and policies continue to reference WCAG 2 versions.
Is WCAG a legal requirement?
WCAG is often referenced in legal matters, such as the U.S. Department of Justice (DOJ)'s enforcement of the Americans with Disabilities Act (ADA), and it's embedded in accessibility laws and standards around the world.
WCAG compliance vs. WCAG conformance
“WCAG compliance” is one of the most common ways people describe meeting the guidelines. Technically, though, WCAG itself is not a piece of legislation, so there's no such thing as complying with it. Organizations comply with laws. They conform to standards.
Put simply, you conform to WCAG, and conforming to WCAG helps you comply with laws like the ADA, Section 508, the AODA, and the EAA. Many of those laws point to WCAG, directly or through other technical standards, to define accessible digital content. That's why WCAG conformance is the global best practice for compliance.
The ADA is a civil rights law that prohibits discrimination against people with disabilities. Under Title II, which covers state and local government agencies, the DOJ’s 2024 rule adopts WCAG 2.1 Level AA as the technical standard for web content and mobile apps.
Section 508 of the Rehabilitation Act of 1973 requires federal agencies to make their information and communication technology accessible. The Section 508 standards incorporate WCAG 2.0 Level AA for web content and digital services.
In Canada, the AODA requires designated public sector organizations and businesses with 50 or more employees in Ontario to make their websites conform with WCAG 2.0 Level AA, with limited exceptions.
The presumptive standard for the European Accessibility Act (EAA), EN 301 549, includes WCAG 2.1 Level AA requirements for web content. The EAA’s requirements have applied to covered products and services since June 28, 2025.
Some U.S. states set their own accessibility requirements. For example, California Assembly Bill 434 requires state agency websites to conform with WCAG 2.0 Level AA or a later version.
How do you meet WCAG?
The most common WCAG failures on home pages, such as low-contrast text, missing alt text, missing form labels, and empty links, are also among the most fixable, according to the WebAIM Million.
Sustained conformance means building accessibility into every stage of digital experience creation, from design to deployment. Here are 15 WCAG best practices your web team can implement:
Provide captions and audio description for multimedia
Captions are critical for making multimedia accessible to people who are Deaf or hard-of-hearing, and can also make content easier to understand for a much broader range of users. Audio description provides access to video content for users with visual disabilities.
Ensure keyboard accessibility
Make all functionality available via keyboard, with no keyboard traps.
Make interactive elements easily identifiable
Make buttons and links easy to spot and use, especially for keyboard users and people with visual and cognitive disabilities.
Use an accessible font type and size
Choose readable font styles and sizes so all users can easily understand text.
Add image alt text
Descriptive text alternatives for non-decorative images allow screen reader users to understand visual content.
Write descriptive anchor text
Use link text that explains the destination or purpose of the link.
Ensure compatibility with assistive technologies
Test with screen readers, magnifiers, and speech recognition software.
Provide sufficient color contrast
Adequate contrast between text and background is essential for users who have low vision or color blindness.
Provide accessible form fields
Proper labels and focus states help all visitors, including screen reader users, complete forms.
Design for mobile accessibility
Make your website and mobile applications accessible on mobile devices, for touch navigation and smaller screens.
Provide transcripts for pre-recorded audio
A transcript gives people who are Deaf or hard of hearing, and anyone who can’t turn on their sound, a media alternative.
Make text resizable
Users should be able to resize text up to 200 percent without losing content or functionality.
Give users control over time limits and motion
Let users turn off, adjust, or extend time limits, pause media that plays automatically, and avoid flashing content.
Keep navigation consistent
Place repeated elements, like the main navigation, in the same place on every page.
Use proper heading and table structure
Use heading levels in logical order and mark up data tables with header cells so screen reader users understand how content is organized.
How do you test for WCAG conformance?
An automated scanning tool, also known as an “accessibility checker,” is a great first step. Automated scans rapidly identify many common WCAG violations and give you a baseline understanding of your website's accessibility. However, they can't catch everything, and your site may contain barriers a scan won't detect.
For this reason, it's wise to partner with digital accessibility experts who can conduct a more thorough evaluation using manual auditing and functional testing across web pages, mobile apps, and documents. They can also help you prioritize and remediate findings.
Why does web accessibility matter?
There are 1.3 billion people worldwide who live with disabilities, including auditory, cognitive, neurological, physical, speech, and visual disabilities. People may rely on screen readers, keyboard navigation, voice commands, captions, or transcripts to use the web.
Digital accessibility is all about making sure everyone, especially those with disabilities, can fully participate in online spaces. Yet accessibility barriers are widespread. According to the 2026 WebAIM Million report, 95.9% of the top one million home pages had detected WCAG 2 failures. There’s a significant gap between the volume of digital content available, and the volume of content that’s usable for people with disabilities.
Following success criteria outlined in WCAG is critical to designing and developing digital offerings that work for all users.
Keep your WCAG conformance on track
Websites constantly evolve, so maintaining accessibility involves regular testing against WCAG success criteria.
A trusted accessibility partner can help you find gaps, prioritize fixes, and build accessibility into your workflows. Start with a free risk assessment to understand your digital accessibility health score based on WCAG, and chart a clear path toward compliance with the ADA, EAA, and other applicable laws.
Frequently asked questions
What does WCAG stand for?
WCAG stands for Web Content Accessibility Guidelines. The guidelines are published by the World Wide Web Consortium (W3C) through its Web Accessibility Initiative, and they are the international standard for making websites, apps and digital documents accessible to people with disabilities. WCAG is a technical standard, not a law, but accessibility laws around the world use it as their benchmark.
What is WCAG compliance?
WCAG compliance means a website or app meets the success criteria of the Web Content Accessibility Guidelines, usually at Level AA. The W3C’s own term is conformance, because WCAG is a voluntary technical standard and not a law. Laws such as the ADA, Section 508, the AODA and the European Accessibility Act point to WCAG, so conforming to WCAG is the accepted way to work toward meeting those legal requirements.
How many versions of WCAG are there?
There are four published versions of WCAG: 1.0 (1999), 2.0 (2008), 2.1 (2018) and 2.2 (2023). A fifth, WCAG 3.0, is a W3C Working Draft and is not yet a standard. Each 2.x version builds on the one before it, so content that conforms to WCAG 2.2 also conforms to 2.1 and 2.0.
What are the new WCAG standards for 2026?
No new version of WCAG has been published in 2026. WCAG 2.2, published in October 2023, is still the current standard. What changed in 2026 is the legal timeline. The U.S. Department of Justice (DOJ) extended the ADA Title II deadline for state and local governments to meet WCAG 2.1 Level AA to April 26, 2027 for entities serving 50,000 or more people, and to April 26, 2028 for smaller entities and special districts. The W3C also published an updated WCAG 3.0 Working Draft in September 2026, but it remains a draft and the W3C says it still has several years of work ahead.
What is the difference between WCAG 2.1 and WCAG 2.2?
WCAG 2.2 adds nine success criteria to WCAG 2.1 and removes one, 4.1.1 Parsing, which is now obsolete. Six of the nine apply at Level A or AA: Focus Not Obscured (Minimum), Dragging Movements, Target Size (Minimum), Consistent Help, Redundant Entry and Accessible Authentication (Minimum). The other three are Level AAA. Everything else in 2.1 carries over unchanged, so a site that meets 2.2 also meets 2.1.
Is WCAG 2.2 a legal requirement?
Not yet in the main U.S. laws, but it is arriving elsewhere. The ADA Title II rule requires WCAG 2.1 Level AA and Section 508 references WCAG 2.0 Level AA; neither names 2.2. In Europe, the newest version of EN 301 549, the standard behind the European Accessibility Act, incorporates WCAG 2.2. WCAG 2.2 is backward compatible, so building to 2.2 Level AA meets the older versions too.
Is WCAG a legal requirement?
WCAG is not a law, but many accessibility laws use it as their technical standard. In the United States, the ADA Title II rule for state and local governments requires WCAG 2.1 Level AA, and Section 508 references WCAG 2.0 Level AA for federal agencies. Ontario’s AODA and EN 301 549, the standard behind the European Accessibility Act, also build on WCAG guidelines. Level AA is the level these laws point to.
Does WCAG apply to mobile apps?
Yes. WCAG applies to mobile apps as well as websites. WCAG 2.1 and 2.2 added specific success criteria written with mobile in mind. These guidelines cover screen orientation, reflow, pointer gestures, and target size. The W3C also publishes guidance on applying WCAG 2.2 to mobile applications, known as WCAG2Mobile. Laws that reference WCAG, including the ADA Title II rule, cover mobile apps too.