The JavaScript program below presents a file upload button. When the user selects a valid FAT12 disk image and uploads it, the contents of the disk's root directory will be displayed. The user can then click the Download button next to a displayed file to download a copy of that file to their local system. Other buttons make it possible to navigate down into subdirectories and, from there, back up to parent directories.

To see the code the source code, leave a comment, or get instructions on how to build your own disk image, visit https://thiscouldbebetter.wordpress.com/2014/07/02/a-fat12-disk-image-explorer-in-javascript/.