The Privacy Cleaner Opera extension enables you to delete cookies in a very easy way. Once you install the extension, all you need to do is to click on the extension's button, next to the URL bar, and select what you want to clean and click on the Clean... button.
To delete cookies in the Google browser, press the Ctrl + Shift + Delete keys and check (tick) only the check box next to Cookies and other site and plugin data. Then, select the time range, by clicking on the drop-down menu next to Obliterate the following items from:, and click on Clear browsing data.
Use Ctrl+Shift+Delete keyboard shortcut [Firefox]
To delete cookies in Firefox, press the Ctrl + Shift + Delete keys and check (tick) the check box next to Cookies. Then, select the time range, by clicking on the drop-down menu next to Time range to clear, and click on Clear Now.
The Click&Clean extension for Google Chrome will help you delete cookies in an easy way. All you need to do is to click on the extension button (upper right corner of the browser) and select the little trash can on the cookies button.