Desktop Browsers

From the History menu, select Clear Recent History.
If the menu bar is hidden, press Alt to make it visible.
From the Time range to clear: drop-down menu, select the desired range; to clear your entire cache, select Everything.
Next to "Details", click the down arrow to choose which elements of the history to clear; to clear your entire cache, select all items.
Click Clear Now.
Exit/quit all browser windows and re-open the browser.

Select Tools (via the Gear Icon) > Safety > Delete browsing history....
If the menu bar is hidden, press Alt to make it visible.
Deselect Preserve Favorites website data, and select:
- Temporary Internet files or Temporary Internet files and website files
- Cookies or Cookies and website data
- History
Click Delete. You will see a confirmation at the bottom of the window when the process is complete.
Exit/quit all browser windows and re-open the browser.

From the Opera menu, select Settings, and then Delete Private Data....
In the dialog box that opens, select the items you want to clear, and then click Delete.
Exit/quit all browser windows and re-open the browser.

From the Safari menu, select Reset Safari....
Select the items you want to reset, and then click Reset. As of Safari 5.1, Remove all website data includes both cookies and cache.
Go to Safari > Quit Safari or press Command-Q to exit the browser completely.

Clearing Cache in Desktop Browsers