In order to be cautious, cPanel does not turn this compression on automatically as there is a small chance that some websites will break with it on. However, if your site does break you can always turn it off really easily and then turn it on later for only some file types.
To turn on the compression, follow these steps:
- Log into cPanel
- Go to the Software tab (halfway down) and click on “Optimize Website”
- Click on “Compress All Content” and then the “Update Settings” button at bottom
- Test that your site still works on a desktop (PC/Mac) and mobile (iDevice/Android)
- You’re done!
This does speed up some websites enormously, particularly when you’re on slow internet connections, yet other websites don’t notice it as much. Nevertheless, we do recommend you turn it on for your site so long as it works. When you do turn it on, we strongly suggest you test on a desktop browser and on a mobile device just to make sure everything does work. Viewing the key pages on your site is really important. The good news is that nearly all modern sites benefit and work with it.
Just so you have some idea of whether it helped much or not it’s quite a good idea to run a test at www.webpagetest.org before and after and compare. (We recommend logging in to webpagetest so your page speed history is retained).