Are all Web users today using Javascript-enabled browsers?

Most Web users today, including screen reader users, have JavaScript enabled in their browsers. WebAIM, in their fifth Screen Reader User Survey (2014) found that 97.6% of survey respondents had JavaScript enabled. This is a solid majority of users, but not all users.

There may be users, both with and without disabilities, who are using technologies that do not support scripting languages due to limited bandwidth, data caps, or other reasons. Sometimes, users and organizations disable scripts in their browsers in order to eliminate possible security risks associated with client-side scripts. 

Therefore, it is important that a website be available to everyone, regardless of whether JavaScript (or another scripting language) is disabled or unavailable for another reason. The site should make its basic functions available to all, but then enhance the experience by deploying scripts. This idea is commonly known as Progressive Enhancement.

Current and recent versions of all major web browsers have integrated support for scripting languages. Assistive technologies can take advantage of correctly coded scripts to improve the web experience for those who use them. This includes, for example, implementing Accessible Rich Internet Applications (WAI-ARIA) together with well-formed Javascript. When coding a site, it is especially helpful to assure that keyboard handlers and appropriate focus management are incorporated so that those who do not use a mouse are able to navigate the site as they expect.

To learn more about using ARIA and Javascript successfully, see several articles on the subject posted on the WebAIM site. A good place to start is with Accessible Rich Internet Applications. For additional information about scripting and accessibility, see our Knowledge Base article How do scripting languages affect accessibility?.