The default physical location is $HOME/Library/Containers/com.docker.docker/Data/com.docker.driver.amd64-linux/Docker.qcow2 as @badonk mentioned. But you can change and specify a new “Disk Image Location” using Docker Desktop on your Mac as follows: Docker Desktop -> Preferences -> Disk [Tab] -> Move Disk Image. However, if you attempt to move the disk image to a location that already has one, you get a prompt asking if you want to use the existing image or replace it. You can find more information here on Docker official pages.