What Are the Levels of WCAG Compliance?

What Are the Levels of WCAG Compliance?

When it comes to accessibility compliance, the Web Content Accessibility Guidelines (WCAG) version 2.0 is the most widely used standard worldwide. WCAG has set internationally shared standards for web content accessibility to meet the needs of individuals, organizations, and governments. Web Content applies to all content on a web page or application, including text, images, sounds, code, or markup that define a website’s structure or presentation.

There are three levels of WCAG compliance: A, AA, and AAA. Although this distinction is essential, it can be baffling. Therefore, we will discuss what WCAG A, AA, and AAA are, what they mean for your site, and which compliance level to aim for when becoming accessible.

Learn more about WCAG and ADA Web Accessibility Standards

What are the WCAG Levels?

There are three compliance levels within WCAG 2.0: A, AA, and AAA. For a website to be accessible for all users, each level’s requirments must be met. The distinction between conformance levels gives an organized structure requiring an increasingly higher standard of accessibility. The three levels provide flexibility upon different situations. For example, in complex websites or advancing technologies, to maintain a minimum level of compliance.

WCAG Foundation Principles

Each level of compliance is based on the same four principles of web accessibility. These principles are the foundations for content on the web and anyone wanting to use it. WCAG 2.0 guidelines follow these four principles: perceivable, operable, understandable, and robust, referred to as POUR. Therefore, to understand each WCAG level, it is essential to start with their foundation. 


A website’s information and elements must be apparent to the user, leaving nothing undetectable or invisible. Most users perceive content and elements on a website through visuals. However, sound or touch are used alternatively for those unable to. 


A website’s interactive elements such as controls, buttons, and navigations should be operable by all users. Users must operate the interface elements by first identifying those elements and selecting those options. Most users can interact by clicking, tapping, swiping, or rolling. However, users who cannot physically click require voice commands or other assistive devices to engage with interactive elements. 


Websites must be clear and concise in presenting predictable patterns for interaction and design. Users should have no issue comprehending the meaning or purpose of the presented information, including the function of buttons or other elements on a website. Everything should have a purpose and should be recognizable to all users.


Content must be robust enough for users to understand the function and reliably use various assisting technologies. 

What Do the Different WCAG Conformance Levels Mean?

As previously mentioned, WCAG 2.0 A, AA, and AAA all have specific criteria to be met. The requirements for a website include all interactive elements, content, and presentation following four principles of POUR. WCAG does provide guidelines for each level for what an accessible website should do, each level building upon the next. However, the specific actions each website must take to be considered accessible or reach a certain level of compliance are not outlined. The most significant difference between conformance levels A, AA, and AAA is what they mean for the users of each website. 

WCAG 2.0 Level A: Minimal Compliance

Level A covers the basic requirements and is the minimum degree of accessibility for a website to be accessible. Basic requirements to meet Level A do not impact the design or structure of the website. Failure to fulfill will result in an inaccessible website and will be impossible or exceedingly difficult for users with disabilities to use.

Notable WCAG 2.0 Level A success criteria include:

  • All non-text content such as audio, video, or images must have a text alternative such as an alt text within the website’s code or captions to serve as an equivalent source for information and context. 
  • Users can effectively navigate the website using only keyboard inputs.
  • Time-based media or video content must have a media alternative for text. 
  • Content and interface elements conveyed through presentation can be extracted and presented to the user in different modalities through assistive technologies or user agents.
  • Color is not used as the only visual means of conveying information, prompting a response, distinguishing an element, or indicating an action by the user.

WCAG 2.0 Level AA: Acceptable Compliance

Level A conformance is an excellent starting point. However, Level AA goes further by ensuring a website must be deemed usable and understandable for most people, regardless of ability. For this reason, level AA compliance has been the standard for accessibility and web accessibility laws globally, including the ADA and Section 508 in the United States. 

Notable WCAG 2.0 Level AA success criteria include:

  • Text for content, captions, and text images can be resized without assistive technology up to 200% without loss of range of function.
  • Text or alt text is used to convey information or content rather than images with text.
  • More than one way to locate a web page within a website except when the web page is the result of a process or steps
  • Navigation elements are consistent throughout the site
  • Form fields have accurate labels

WCAG 2.0 Level AAA: Completely Compliant

Compliance at WCAG 2.0 is the highest level of accessibility and accommodates the maximum number of users. Unfortunately, it is also the most challenging level to achieve. While this level of compliance would be ideal, it is not necessary., W3 states they do not recommend or require Level AAA compliance for an entire website since it is impossible to achieve Level AAA from some content.

Notable WCAG 2.0 Level AAA success criteria include:

  • Sign language interpretation for audio or video content
  • Visual presentation of text and images has a contrast ratio of at least 7:1 except for large text, logo, or visual decorative components with no significance to the content.
  • Timing is not an essential part of any activity on the website. 
  • The website does not contain anything that flashes more than three times in any one second.
  • Context-sensitive help is available.

Can You Partially Meet a WCAG Level?

A website must meet all of the accessibility compliance level’s guidelines. To state that a website is Level AA compliant, it must meet every requirement for both Level A and the Level AA guidelines. Therefore, if you meet the24 out of 25 requirements for Level AA, your site will still be deemed only a Level A. However, please do not use this not to try to aim for higher levels of compliance. The more accessible your site is, the better the user experience is for your users regardless of their abilities.

What WCAG Level to Aim For

Most websites and development teams aim to meet Level AA. The legally required level for legislation for specific sites is Level AA, including the ADA and Section 508. Suppose you want to strengthen your existing website by making it ADA compliant. In that case, it is best to accomplish the Level A criteria first before progressing to Level AA. A Level A compliance level is still more accessible than an inaccessible website.


Understanding the different levels of WCAG 2.0 and their requirements can serve as a guide when implementing accessibility into your website. Take the first steps towards becoming accessible. Testing and correcting accessibility issues will help better your business and mitigate expensive ADA lawsuits. 

Integrating accessibility can seem intimidating at first, but 216digital  is here to help. If you would like more information on web accessibility or how to make your website accessible today, schedule a 15-minute complimentary consultation with our experts.