Use "Add Images..." button to add images. You can select multiple files
in this window using the control keys.
Or you can simply use the "Add Folder..." button to add all
images from a selected folder.
In the left top corner of Free Image Converter you can see the Conversion Options section.
You can use the default options or select your own.
If you want to select more specific options you can use the "Advance Convert..." option.
Click the "Convert..." button, select a destination folder for the converted
files and wait until all images are converted.
If you're using the advanced conversion option, the destination folder will
be available in the "Advanced Options" window.