HexTool is a GNU GPL Windows (Win95/98/NT/2000/XP) application to provide hexadecimal, decimal and binary number manipulation. The latest version of HexTool now contains IP address fields and an endian flip button. Starting HexTool with a command line option, eg, "hextool 1" will force it to start in Advanced mode. The user can toggle between simple mode and advanced mode using the Maximise/Restore button.