Simple Calculator is a lite addon that renders a simple calculator in toolbar popup UI.
This calculator includes only simple math operations. Just click on the toolbar button to open the UI and start typing your desired math operations.
Please note that all calculations are rounded to at most 7 decimal places. You can type either with your keyboard or the embedded virtual keyboard in popup UI.
In order to report bugs, please fill the bug report form in the addon's homepage (http://mybrowseraddon.com/calculator.html).