IMZ is an older file format that was used to store FDD disk images. A floppy disk image in IMZ format could be generated compressed or uncompressed. It could also be saved as a self-extracting archive in an EXE file. This format helped with duplicating floppy disks and restoring data after a floppy disk failure.

Most often, IMZ files were associated with a program called WinImage, which allowed the management of such data. This tool was used when floppy disks were a popular portable data carrier.