WCAG (Web Content Accessibility Guidelines)
When discussing website accessibility standards, the most common term you may hear is WCAG.
WCAG, the Web Content Accessibility Guidelines, is a set of technical requirements for making web-based content, like websites and web-based applications, accessible for users of every ability—including people with disabilities who use assistive technology. The goal is to provide a single, common global standard for web accessibility.
WCAG guidelines are published by the Web Accessibility Initiative of the World Wide Web Consortium (W3C), which is the main international standards organization for the internet.
WCAG itself is not a piece of legislation, so following its guidelines is referred to as “WCAG conformance” versus “WCAG compliance.” But the WCAG standards have been adopted in numerous global laws, including Section 508 of the Rehabilitation Act of 1973, and the Accessibility for Ontarians with Disabilities Act (AODA). Conformance with WCAG standards is the legal best practice for compliance with most global web accessibility regulations.
Why should my organization follow WCAG standards?
There are tremendous business benefits when your digital experiences conform with WCAG and are accessible to people with disabilities:
- Serve a larger audience: Estimates show that one in four adults in the U.S identifies as having a disability that affects their daily life, including whether they can access digital information. When following WCAG standards, you’re creating digital content that’s accessible to users of every ability, serving the largest possible audience.
- Validate accessible products: If you sell technology, demonstrating WCAG conformance validates a commitment to accessibility, which is required when selling to the public sector and increasingly required in the private sector.
- Reduce legal risk: Following WCAG standards is a best practice when it comes to compliance with applicable accessibility laws. Non-compliance can lead to a costly, time-consuming lawsuit that may tarnish your brand’s reputation.
The WCAG principles
WCAG’s accessibility standards are based on four principles (often referred to as POUR):
- Perceivable = Information and user interface components must be presented to users in ways that they can perceive. For example, it’s important to present information that can be perceived in different ways, where a user can adjust color contrast or font size, or view captions for videos.
- Operable = User interface components and navigation must be functional for users in ways they can operate. For example, a user must be able to perform required interactions using a keyboard or voice commands, not just using a mouse.
- Understandable = Information and user interface operation must be understandable. For example, information and instructions should be clear and navigation methods should be easy to understand and use.
- Robust = Content must be robust enough so that it can be interpreted reliably by a wide variety of users and types of assistive technologies. As technologies evolve, code and content should remain accessible for users of common and current assistive devices and tools.
Let us show you how, or if, your website is meeting these principles of digital accessibility.

WCAG conformance levels
There are three levels of WCAG conformance: A, AA, and AAA. Each level builds on the previous level like a pyramid. So, in order to meet Level AA, you must meet all of Level A, and in order to meet Level AAA, you must meet all of Level AA.
- Level A = This level represents the base level of conformance. Level A criteria affect the broadest group of users with the most benefits and are essential. But, with the base level of support, some barriers will still exist that impact certain groups of users.
- Level AA = This level is the most common target conformance level, often adopted in regulations or negotiated in legal settlements. The criteria at this level establish a level of accessibility that works for more users, including those who use assistive technology
- Level AAA = This is the highest conformance level achievable, meaning it covers the success criteria of all three levels. However, level AAA is not applicable or realistic in all situations. Some organizations may choose to adopt specific criteria at this level.
Which WCAG conformance level should you follow, and how well is your site meeting WCAG accessibility standards?

Keeping up with WCAG standards
As the digital world continues to evolve and technologies advance, WCAG standards also evolve to keep pace. WCAG 2.0 was published in 2008, with WCAG 2.1 updates released in 2018. WCAG 2.2 is scheduled to be published in 2023. Each update is backwards compatible, that is, it builds upon the previous version, with additional standards added.
For example, WCAG 2.1 adds success criteria to 2.0 that improve mobile (and other small screen) experiences, and enhancements for people with low vision, motor and dexterity disabilities, and cognitive disabilities. WCAG 2.2 will add additional success criteria building upon those in 2.1.
Because of this backwards compatibility, if your website conforms with WCAG 2.1, it also conforms with WCAG 2.0, for example.
Many aspects of WCAG compatibility synchronize with ADA and AODA compliance. Meeting the accessibility standards for one law will put an organization on the right track to meeting the other.
The W3C encourages organizations to conform with the most recent version of WCAG as a best practice. This will not only provide improved accessibility for every user, it will ensure your organization is up-to-date in its legal digital accessibility compliance efforts.

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Request an assessmentFrequently asked questions
Is WCAG a legal requirement?
The Web Content Accessibility Guidelines (WCAG) are not a law. However, some laws, including Section 508 of the Rehabilitation Act of 1973 and the AODA explicitly cite WCAG conformance as an accessibility requirement. Furthermore, the Department of Justice has referenced WCAG standards in its web accessibility enforcement actions. WCAG is considered the global gold standard for web accessibility, so even though WCAG conformance is not a law, following WCAG standards is the most effective way to achieve web accessibility and comply with certain legal mandates.
What is WCAG compliance?
Because WCAG itself is not a law, “WCAG compliance” is technically an incorrect term. Aligning with WCAG standards is referred to as WCAG conformance. WCAG is considered the global gold standard for web accessibility, and some laws cite it explicitly as a guideline for making web content accessible. Consequently, conformance with WCAG will help comply with legal mandates.
Does WCAG apply to mobile apps?
WCAG provides a comprehensive set of criteria for accessible digital content. It was originally created for HTML-based experiences, but adhering to WCAG success criteria is also the best-practice for all types of digital experiences, including mobile apps. Specifically, WCAG 2.1 includes criteria for tablets and mobile devices.