Lets start by understanding what is a browser cache.
Complex Method: Let's start with Google Chrome:
Click on the Chrome menu on the browser toolbar.
Select Clear browsing data.
A dialogue window will appear, providing you with a list of checkboxes for the types of information that you wish to have removed.
You can also set how far back in your browsers history you wish to have removed.
Once, you have selected the types of information you wish to remove, click Clear browsing data.
Simple Method: Google chrome force cache clear:
When hiting the desired website you can press ctrl+shift+r and chrome will do a forced flush of the cache.
Complex Method: Safari on a Mac (only)
Click the Safari menu and select Empty Cache.
Click the Empty button in the dialog box that appears to confirm the deletion of your cache.
When your computer is finished, close all instances of Safari. Launch a new Safari browser window.
Simple Method: Safari force cache clear:
When hiting the desired website you can press cmd+r and safari will do a forced flush of the cache (Mac Only)
When hiting the desired website you can press Ctrl + F5 and safari will do a forced flush of the cache (Pc Only)