Developers are responsible for testing their websites and applications against the three most recent versions of commonly used browsers, listed below. Developers should test these browsers on multiple platforms.

Commonly Used Web Browsers

The data for the most commonly used Web browsers by visitors to are:

Browser Jan. – June 2015 July – Dec. 2014 Jan. – June 2014 July – Dec. 2013
Chrome 37.8% 36.1% 31.9% 27.9%
Safari 27.5% 25.6% 25.4% 28.1%
Firefox 16.5% 18.9% 19.5% 20.4%
Internet Explorer 15.4% 15.8% 19.6% 19.5%

Developers may test against less commonly used browsers but are not required to do so.

Develop for Your Community

In addition to testing against the most commonly used browsers and platforms, developers are also responsible for testing their sites and applications according to their target audience. If developers are creating or maintaining content or applications that have a specific target audience, e.g., K-12 teachers, they should determine what their browser usage is for that audience and make testing decisions based on that data.

In rare circumstances, some campus applications may not support all of the commonly used browsers due to special application needs or possible bugs in the browsers. Developers should clearly inform users if that is the case with their application.

Developers are discouraged from implementing any browser-specific features that do not break gracefully in all commonly used browsers.

Up-to-date Browsers

In addition to testing against popular browsers, developers should ensure their own browsers are up-to-date and secure by regularly downloading and installing patches and updates.