Changing File Extension of Single or Multiple Files is now made easy with Daanav File Extension Change. This File Management Utility allows you to navigate to any selected folder on your hard drive, visually see folder contents and change file extension of files located in selected folder and it?s sub folders. This Free File Extension Changer for Windows presents a simple user interface as captured on a Windows 8 Computer below. You can easily navigate to your desired folder containing files whose extension you want to be changed. Once you have found your way to the desired folder, all you need to do is define the old file extension and then new file extension and start the process of changing file extensions.