One of the major goals web developers have when building web applications is performance. In general there are three areas that can be improved to achieve better overall performance:

  • the server-side generation of the requested page,
  • the time it takes for the page and all of its web resources to be downloaded by the browser and
  • the performance of the rendered page in the browser.

RadControls for ASP.NET AJAX have been, are, and will continue to be Telerik's promise for easily building great ASP.NET web applications, which are both beautiful and performant. There was however a small area where the tools lacked behind - CSS minification. Until now, that is.

Starting with Q1 2012 BETA all of our CSS code, both embedded and on the CDN, ships minified. Here is a comparison of the sizes of the three largest uncompressed RadControls CSS files before and after minifying:


CSS file

Size (not minified)

Size (minified)

Size reduced by













As you can see these are relatively small files, and the rest of RadControls' style sheets are even smaller, so on a page with lots of RadControls the difference between not minified and minified CSS will be small, yet noticable.

For instance, in our Event Scheduler demo's front page the browser downloads 198.2KB of embedded, not minified CSS. 

Not minified CSS

With minification you save 32.9KB.

Minified CSS

However, in large real-world web applications there are lot more custom style sheets. Then it is always a good idea to squeeze out those extra bytes and reduce the size of your styles (and scripts for that matter) as much as possible by minifying and compressing.

In addition you can use RadStyleSheetManager to combine external style sheets so that you can reduce all CSS requests, embedded and external, into one!

Telerik ASP.NET AJAX Q1 2012 Beta is here

About the Author

Simeon Panayotov

is one of the tech leads in the Windows 8 HTML team at Telerik. Previously he has been a Team Lead of one of the ASP.NET AJAX teams and is now transferring knowledge and experience to the Windows 8 platform. Although his focus is on HTML and JavaScript, he doesn't limit himself to these languages and is exploring Python, C/C++, C# in his free time. He loves reading sci-fi and humorous novels and stories. He is an avid music lover.


Related Posts


Comments are disabled in preview mode.