Main content

Progressive enhancement

The core purpose of every document must not require JavaScript or CSS to function.


We aim to provide a core experience to as broad an audience as possible, allowing users to choose the software and devices that work best for them in a broad range of circumstances.

Equally a robust site or application in the more traditional sense minimises its dependencies. The minimum dependency for a web site should be an internet connection and the ability to parse HTML.

For this reason all BBC documents must enable their core purpose without relying on CSS or JavaScript.

CSS and JavaScript can, and should, be used to enhance the user experience beyond this basic level. For example, a ‘live’ page has a core purpose to provide the latest content about an event to the user. The core experience is the latest content at the time of the request. The experience enhanced with JavaScript automatically updates this content without the user having to take action.


Core experience

The experience that is provided to users without CSS or JavaScript.



Procedure Expected Result Type
View the page with JavaScript and CSS disabled Verify that all core content is available and functional Manual

More in this category: « Visible on focus Control styles »