As mentioned, an IPSW is a disguised ZIP file. The first extraction layer is straightforward.
pzb -g Firmware/dfu/iBSS.d321.RELEASE.im4p http://apple.com/firmware/iPhone.ipsw extract ipsw file
While this method gives you access to the files, the most important data is often locked inside the DMG files, which leads us to more advanced extraction methods. As mentioned, an IPSW is a disguised ZIP file
: Frequently cited as the "best free tool." Users highlight that you can right-click an IPSW and select "Open archive" without even renaming the file. It is praised for being lightweight and handling the DMG files inside the IPSW better than Windows' native explorer. extract ipsw file