There are reasons to clear your browser's cookies too, but we're going to focus on the cache here. This is how to do the job no matter what browser you're using.

To clear cache accumulated from applications on Mac, navigate to Finder, hold the Shift, Command and G buttons simultaneously, insert ~/Library/Caches in the tab provided to view your cache files ...

You can clear the cache on your Chromebook in just a few steps. It's a good idea to clear the cache on your Chromebook every so often to keep your computer running smoothly.