How to make websites more accessible—understanding WCAG standards

The four fundamental principles of WCAG

The fundamental principles of WCAG (Web Content Accessibility Guidelines) are the cornerstone concepts that underpin the guidelines and drive their implementation. These principles are designed to ensure that digital content is accessible to all users, including those with disabilities. The four fundamental principles of WCAG are as follows:

Perceivable: Information and user interface components must be presented in ways that users can perceive. This principle emphasizes the importance of making content available to users in various sensory modalities. For example, consider a web page containing a photograph of downtown Warsaw at sunset. Without alt text, a screen reader user would not know what the image depicts. However, adding alt text such as “A colorful sunset over a Warsaw city skyline” helps individuals using screen readers to perceive the content of the image and gain a better understanding of the web page’s context.

Operable: The user interface components and navigation must be operable by all users, including those with mobility impairments. This principle focuses on ensuring that users can interact with content and navigate through websites using various input methods, such as keyboard, mouse, or touch. Providing keyboard accessibility and allowing users enough time to complete tasks are examples of operable design considerations. Imagine a user with a mobility impairment who cannot use a mouse due to limited dexterity. They navigate to a website to complete a form and submit an inquiry. In order to do this effectively, the website must allow them to:

• tab through the interactive elements on the page, such as links and form fields, in a logical order;
• use the Enter key to activate buttons and submit forms;
• receive clear visual focus indicators (e.g., highlighting or underlining) as they navigate through each element using the keyboard;
• navigate back and forth within drop-down menus and select options using the keyboard alone.

If any of these elements are not operable via keyboard alone, a user with mobility impairments would encounter barriers in accessing and interacting with the website.

Understandable: Information presented and the operation of the user interface must be understandable. This principle emphasizes the importance of presenting content in a clear and intuitive manner, making it easy for users to comprehend and navigate. Using plain language, providing consistent navigation, and offering clear instructions help users understand and interact with content effectively. Here’s an example of an understandable error message:

“Oops! It looks like the password you entered is too short. Please enter a password with at least 8 characters.”

In this example, the error message clearly identifies the issue (a short password) and provides guidance on how to resolve it (enter a password with at least eight characters). The language used is simple and straightforward, making it easy for the user to understand what went wrong and how to fix it.

In contrast, an unclear or ambiguous error message, such as “Error: Invalid input,” would not provide sufficient information for the user to understand the problem and take appropriate action.

Robust: Content should be robust enough to be consistently interpreted by a broad range of user agents, including assistive technologies. This principle guarantees that digital content remains accessible amid evolving technologies. Utilizing standard markup languages, adhering to coding best practices, and thoroughly testing content on various browsers and devices are essential for maintaining robust accessibility.

Consider a website that has been developed using modern web technologies and standards. While it may work perfectly in the latest version of popular web browsers like Google Chrome or Mozilla Firefox, it may not function properly in older browsers or alternative browsers used by some individuals, such as Internet Explorer or Safari.

Additionally, users with disabilities often rely on assistive technologies like screen readers or braille displays to access web content. It’s essential that websites are compatible with these assistive technologies so that users with disabilities can navigate and interact with the content effectively.

These four principles serve as the foundation for the WCAG guidelines and guide developers, designers, and content creators in creating accessible digital experiences for all users, regardless of their abilities or the technologies they use.

Levels of conformance

WCAG (Web Content Accessibility Guidelines) standards are organized into three levels of conformance, often referred to as A, AA, and AAA. These levels indicate the degree to which a website or other digital content conforms to the WCAG guidelines, with each level representing a progressively higher standard of accessibility. Here’s an overview of each level:

• Level A (minimum conformance): Level A conformance addresses the most basic and essential accessibility requirements. Meeting Level A criteria ensures that the content is accessible to some extent, but it may still have significant barriers for some users with disabilities. Level A guidelines typically include fundamental accessibility features that are relatively easy to implement and have a significant impact on accessibility.
• Level AA (intermediate conformance): Level AA conformance builds upon Level A by addressing additional accessibility requirements that enhance the usability and accessibility of content for a broader range of users with disabilities. Meeting Level AA criteria ensures a higher level of accessibility and a more inclusive user experience. Level AA guidelines cover a wider range of accessibility features and often involve more complex implementation.
• Level AAA (maximum conformance): Level AAA conformance represents the highest level of accessibility and encompasses the most stringent accessibility requirements. Meeting Level AAA criteria ensures the highest degree of accessibility and usability for users with disabilities. Level AAA guidelines include advanced accessibility features and may require significant effort and resources to implement fully.

It is important to note that achieving conformance with higher levels of WCAG does not necessarily mean that a website or digital content is perfectly accessible to all users. However, adhering to higher levels of conformance increases the likelihood that the content will be accessible to a broader range of users with disabilities and provides a more inclusive user experience overall.

Many organizations aim for at least Level AA conformance to ensure a reasonable level of accessibility for their websites and digital content. However, the specific level of conformance pursued may depend on factors such as legal requirements, organizational priorities, and the target audience’s accessibility needs.