The information presented within this glossary entry is aimed at website owners seeking to learn the ropes of web accessibility. Technical elements are described in layman’s terms, and, as a rule, all topics pertaining to the legalities of web accessibility are presented in as simplified a manner as possible. This guide has no legal bearing, and cannot be relied on in the case of litigation.

The Web Content Accessibility Guidelines, commonly known as WCAG, are a set of guidelines designed to make web content more accessible to people with disabilities. This framework provides ‌clear direction for web developers and designers, ensuring that the internet is an inclusive space for everyone, including those with diverse needs. Since its release, WCAG has significantly influenced international web accessibility policy, often being adopted as the standard for compliance in various regions.

Originating from the Web Accessibility Initiative (WAI) of the World Wide Web Consortium (W3C), WCAG has become a cornerstone in the push for digital accessibility. The W3C, an international community that develops open standards, recognized the need for a comprehensive set of guidelines to ensure the long-term growth of the web in an inclusive manner, leading to the creation of WCAG.

WCAG versions and updates

The Web Content Accessibility Guidelines (WCAG) have undergone several iterations since their inception, reflecting the evolving nature of web technologies and the growing understanding of accessibility needs.

WCAG 2.0, released on December 11, 2008, set the foundation for modern web accessibility standards. It was followed by WCAG 2.1, which was published on June 5, 2018 and later updated on September 21, 2023. This version introduced additional success criteria to address gaps in the original guidelines. All WCAG 2.0 requirements are included in WCAG 2.1, making it backward-compatible. The initial draft of WCAG 2.2 was introduced in February 2020, and after a series of refinements based on feedback and advancements in web technologies, it was officially published on October 5th, 2023, bringing with it further enhancements to address contemporary web accessibility challenges.

Core principles of WCAG

At the heart of WCAG lies a set of four principles that serve as the foundation for creating accessible web content. These principles ensure that web content is not only usable by people with permanent disabilities but also by those with temporary or situational disabilities.

  1. Perceivable: This principle emphasizes that information and user interface components must be presented in ways users can perceive. In essence, users should be able to recognize and comprehend the information being presented, regardless of whether they have a disability. For instance, providing text alternatives for non-text content ensures that those with vision impairments (e.g., low vision) can perceive the content through screen readers (e.g., JAWS and NVDA)
  2. Operable: Web content should be navigable and usable, meaning that all users, including those with disabilities, should be able to interact with the site or application. This includes ensuring that all functionalities can be accessed via a keyboard for those who cannot use a mouse
  3. Understandable: Information and the operation of the user interface should be clear and straightforward. This means both the content and the navigation should be predictable, and users should be able to comprehend any information or operation on the website
  4. Robust: Web content should be reliable and should be interpreted consistently by a wide range of user agents, including assistive technologies. As technology evolves, the content should remain accessible, ensuring longevity and inclusivity

WCAG conformance levels

WCAG outlines varying degrees of accessibility conformance to cater to the diverse needs of users and the varied capabilities of websites and applications. These levels serve as benchmarks for organizations and developers to gauge the accessibility of their digital content:

  1. Level A: This is the minimum level of conformance. Meeting this level indicates that the web content satisfies the most basic accessibility features, addressing some of the most glaring accessibility barriers that impact various user groups. However, it doesn't mean the web content will be fully accessible to all users
  2. Level AA: Achieving AA conformance means that the web content meets all Level A and Level AA criteria. This level addresses a wider range of accessibility barriers and is often targeted by organizations as it balances comprehensive accessibility with practical implementation. Many legal standards and policies require conformance at this level
  3. Level AAA: This is the highest level of conformance. Meeting Level AAA criteria indicates that the web content has been optimized to be accessible to the widest range of users with disabilities. However, it might not be feasible for all web content to meet this level due to certain design or content complexities

WCAG's technological scope

WCAG was crafted with a broad technological scope in mind, ensuring that they remain relevant and applicable across a diverse range of digital platforms and technologies. These include:

  • Websites: At its core, WCAG was designed to make websites more accessible. This includes everything from static web pages to dynamic, interactive sites
  • Web applications: WCAG offers guidelines for a wide range of web applications, from online forms and shopping carts to the user interfaces of complex web-based applications, such as content management systems (CMS), customer relationship management (CRM) tools, and interactive dashboards
  • Mobile applications: Though WCAG is web-focused, many of its principles and guidelines are applicable to mobile app environments, ensuring a consistent user experience
  • Document formats: Beyond traditional web content, WCAG's principles and guidelines can be applied to ensure the accessibility of web-based documents, such as PDFs, Word documents, and PowerPoint presentations
  • Emerging technologies: As new technologies emerge, the principles of WCAG serve as a foundation to guide their development in an accessible manner. This includes technologies like virtual reality, augmented reality, and other future innovations

WCAG guidelines and success criteria

WCAG is structured around two primary components: guidelines and success criteria. While they are closely related, they serve distinct purposes in the framework of WCAG.

Guidelines provide the overarching principles and general recommendations to ensure web content is accessible. They are broad, general statements about making content accessible and do not provide specific techniques or methods. Instead, they offer a high-level overview of the areas to consider for accessibility.

Success criteria, on the other hand, are specific and testable. They provide a clear measure for determining whether a particular guideline has been met. Each success criterion is associated with one of the WCAG conformance levels (A, AA, or AAA), indicating its relative importance and impact. By meeting the success criteria, developers and designers can be confident that they are adhering to the associated guideline.

Notable WCAG guidelines

  • Text Alternatives (1.1): Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols, or simpler language
  • Time-based media (1.2): Provide alternatives for time-based media, ensuring that audio and video content is accessible through captions, subtitles, or other means
  • Adaptable (1.3): Create content that can be presented in different ways without losing information or structure, ensuring flexibility in presentation
  • Distinguishable (1.4): Make it easier for users to see and hear content, separating foreground from background, ensuring that content stands out and is easily discernible
  • Input Modalities (2.5): Ensure that functionalities can be operated through various input methods beyond the keyboard, catering to a diverse range of user interactions

Notable WCAG success criteria

The WCAG guidelines are accompanied by specific success criteria, which provide a clear measure for determining whether a particular guideline has been met. These criteria are essential for developers, designers, and organizations to ensure their web content is accessible. While there are numerous success criteria across the different versions of WCAG, some have gained particular attention due to their broad applicability and impact. These include, but aren't limited to:

  • Non-text content (1.1.1): All functional and meaningful non-text content should have a text alternative that describes the relevant content and function of all non-text content
  • Keyboard (2.1.1): All functionalities must be operable through a keyboard interface
  • Consistent navigation (3.2.3): Navigational mechanisms, like menus or icons, should be consistent throughout the web content
  • Error prevention (3.3.4): For web pages that cause legal commitments or financial transactions, users should be able to reverse their submission or review and confirm before submitting the form

These are just a few examples, and the full list of guidelines and success criteria is extensive, addressing a wide range of potential barriers to accessibility.

WCAG's role in international web accessibility legislation

WCAG has become a cornerstone in the global effort to make the digital world more inclusive. Recognized for its comprehensive approach to web accessibility, WCAG has influenced and been referenced in numerous international legislations, ensuring that online spaces are accessible to everyone, regardless of their abilities. Among the laws where WCAG holds a pivotal position are:

The Americans with Disabilities Act (ADA)

The Americans with Disabilities Act (ADA) is a pivotal piece of American legislation concerning accessibility and civil rights for individuals with disabilities. It prohibits discrimination based on disability in various facets of daily life. Over the years, a consensus has emerged that the ADA extends to the online domain. Today, U.S. courts apply ADA accessibility requirements to websites, necessitating their compliance with the act. Specifically, ADA Title III, which covers public areas such as banks, colleges, transportation, real estate agencies, and “public accommodations,” requires businesses under this category to ensure accessibility for the disability community. In 2018, the Department of Justice (DOJ) clarified that websites are considered places of public accommodation and should adhere to ADA Title III. This essentially means that almost all businesses fall under this category. While ADA Title III doesn't explicitly detail the steps to make a website accessible, U.S. courts often reference WCAG as the standard for compliance in ADA-related cases.

Section 508 of the Rehabilitation Act

Section 508 is a significant amendment to the Rehabilitation Act of 1973. It mandates that all U.S. federal agencies and any other organization or business that receives federal funding (including service providers to such bodies) ensure their information and communication technology (ICT) is accessible to people with disabilities. This encompasses a wide range of digital content, including websites, email, web-based applications, electronic documents, and multimedia. Section 508 incorporates WCAG 2.0 Level AA as its standards for conformance. This means that not only federal agencies but also contractors, recipients of federal funds, and federally conducted programs and services must ensure their digital content aligns with these guidelines. The overarching goal is to guarantee that all users, especially those with disabilities, can access and use the digital resources provided by these entities.

The Accessibility for Ontarians with Disabilities Act (AODA)

The Accessibility for Ontarians with Disabilities Act (AODA) is a Canadian legislation aiming to create a more accessible Ontario by 2025. The AODA has set various standards, one of which pertains to web accessibility. Under this standard, many organizations in Ontario are required to make web content accessible, adhering to WCAG 2.0 Level AA guidelines, with the exception of success criteria 1.2.4 Live Captions and 1.2.5 Audio Descriptions (Prerecorded). This means businesses and organizations in Ontario must ensure their digital platforms conform to these guidelines to provide an inclusive online experience for all users.

The European Accessibility Act (EAA)

The European Accessibility Act (EAA) is a significant piece of legislation in the European Union that aims to improve the accessibility of products and services across its member states. While the EAA is expected to make web accessibility compulsory by 2025, it's worth noting that the EN 301549 standard, which references WCAG 2.1 Level AA, is already in place in Europe, setting accessibility requirements for ICT products and services.

Testing for WCAG conformance

Testing for WCAG conformance is essential to ensure that digital content is accessible to all users. There are multiple approaches to achieve this. Manual testing involves individuals, often with expertise in accessibility, inspecting websites and applications to identify potential barriers and ensure they meet WCAG criteria. Automated tools, such as accessScan, offer a time-efficient and cost-effective way to scan websites for potential accessibility issues based on WCAG guidelines. They provide a comprehensive overview and can detect a wide range of issues swiftly. Complementing these tools with a manual approach, typically conducted by expert service providers, allows for a deeper dive into specific areas, adding an additional layer of inspection to ensure all nuances are addressed. Therefore, the optimal approach to testing for WCAG conformance combines the efficiency of automated tools with the detailed scrutiny of manual inspection, ensuring a thorough and accurate assessment of accessibility.

#1Automated Web Accessibility Solution for ADA & WCAG Compliance

Drive inclusivity and meet ADA/WCAG guidelines, Try accessWidget for Free!