If you find yourself using the Windows Calculator or Excel often to do simple math operations, a tool you might be interested in is Taskbar Calculator. This free tool does just what you would expect: adds a small calculator to your Windows taskbar.

If you look at the reviews, you can see some users complain that the tool only performs basic functions (add, subtract, multiply and divide) and others complain it takes up too much space. So bear that in mind if you decide to give this tool a try.

Personally, I just have a the shortcut key combination of Ctrl+Alt+C assigned to the calculator and I have found this works for me.