*This article is an English translation of a Japanese article.
WAI-ARIA (Web Accessibility Initiative – Accessible Rich Internet Applications) is a technical specification designed to make web content more accessible. WAI-ARIA plays a critical role in improving the accessibility of dynamic content and complex user interfaces, ensuring that all users, including those with disabilities, can access and interact with web content effectively. This article explains the overview of WAI-ARIA, its key roles and attributes, how to apply it, and best practices for implementation.
1. Overview of WAI-ARIA
WAI-ARIA is a specification developed by the World Wide Web Consortium (W3C) as part of its Web Accessibility Initiative. Its goal is to enhance the accessibility of dynamic content and web applications, particularly for users of assistive technologies such as screen readers. By implementing WAI-ARIA, web content can be interpreted more accurately by assistive technologies, making information more accessible to visually impaired and other users.
Main Objectives
- Improve Accessibility of Dynamic Content: Ensure that content dynamically updated through JavaScript is correctly interpreted by assistive technologies.
- Support for Custom UI Components: Assign appropriate roles and properties to custom interface elements, ensuring they are accessible.
- Provide Accessible Navigation: Facilitate keyboard navigation and support screen readers for better web accessibility.
2. Key Roles and Attributes of WAI-ARIA
WAI-ARIA defines specific roles, properties, and states to improve accessibility. Below are the main components.
2.1 Roles
Roles in WAI-ARIA describe the purpose of a UI component, allowing assistive technologies to interpret them correctly.
- Landmark Roles:
navigation(for navigation),main(for main content),banner(for headers), which help define the major sections of a webpage. - Widget Roles:
button,checkbox,slider, which define interactive elements users can control.
2.2 Properties and States
Properties and states define the characteristics or current conditions of UI elements.
- Properties: Define attributes such as
aria-labelledby(labeling an element) andaria-describedby(providing a description for an element). - States: Represent the current status of an element, such as
aria-checked(indicating if an item is checked) andaria-expanded(showing if a section is expanded or collapsed).
2.3 ARIA Live Regions
Live regions notify assistive technologies when content is dynamically updated. The aria-live property is used for real-time updates, such as displaying alert messages.
3. How to Apply WAI-ARIA
WAI-ARIA is applied by adding attributes to HTML elements, allowing assistive technologies to interpret the roles, properties, and states accurately and provide feedback to users.
3.1 Basic Application Example
<button role="button" aria-pressed="false">Toggle</button>
3.2 Applying Landmark Roles
<nav role="navigation">
<!-- Navigation menu -->
</nav>
Adding role=“navigation” to the <nav> element clarifies that the section serves as a navigation area.
3.3 Enhancing Widgets
Custom UI components can be made accessible using WAI-ARIA attributes.
<div role="slider" aria-valuemin="0" aria-valuemax="100" aria-valuenow="50"></div>
In this slider example, specifying the minimum, maximum, and current values helps assistive technologies interpret the component.
4. Best Practices for Implementing WAI-ARIA
To maximize the effectiveness of WAI-ARIA, follow these best practices:
4.1 Use Only When Necessary
WAI-ARIA should only be used when native HTML semantics cannot provide the needed accessibility. Native HTML elements such as <button> and <header> often include built-in accessibility features, making it easier to ensure compliance.
4.2 Select Appropriate Attributes
WAI-ARIA attributes should be used carefully and appropriately. Incorrect usage can confuse assistive technologies and degrade accessibility.
4.3 Regular Testing and Evaluation
Regularly test accessibility by using assistive technologies such as screen readers. This ensures that your content works as intended and meets the needs of all users.
4.4 Provide Fallbacks
Design with accessibility in mind, ensuring that your site works even in environments where WAI-ARIA is not supported. Fallback mechanisms ensure that basic functionality is always available.
WAI-ARIA is a powerful tool for enhancing web accessibility, but it must be used correctly to achieve the best results. By combining standard HTML elements with WAI-ARIA attributes where needed, web developers can create inclusive web experiences for all users. Implementing WAI-ARIA is an essential step in building accessible websites, making it a key element in achieving a fully inclusive web.
We have released the UUU Web Accessibility Widget Tool, designed to make web accessibility easy to implement. This tool helps improve the accessibility of websites quickly and efficiently, even without specialized knowledge.
If you’re interested in enhancing your website’s accessibility, please check out the details. We are here to support you in making your website more user-friendly and accessible to a wider audience.