Paste your uncompressed CSS in the first textbox and click on button "Minify CSS", wait for few seconds and you should get minified CSS in the second text-box, copy it and use it to save your server bandwidth for free.
Benefits of minified code(CSS/HTML/JS)
Users load content faster as less unnecessary data needs to be downloaded. Users experience identical service without the additional overhead.
Businesses see lower bandwidth costs as less data is transmitted over the network. The extra content that only developers care about is no longer being sent to users