There are 6 file types use the .IMG file extension:
- Disc Image Data File
- Macintosh Disk Image
- ERDAS IMAGINE Image File
- Floppy Disk Image
- Garmin Map File
- GEM Image
1. Disc Image Data File
An IMG file is a disk image file created by various disk imaging applications, such as H+H Software Virtual CD. It stores an exact copy of the data on a CD or DVD and is used for backups and burning new discs.
IMG files created by different disk imaging programs may use different formats. For example, IMG files created by SlySoft CloneCD must be paired with an associated .CCD and .SUB file before they can be used to create a disc. Before using an IMG file to create a new disc, you should attempt to determine what program created the IMG file and check whether your disc-authoring program can burn files saved in that format.
You can use IMG files to create discs in several Windows programs, including:
- H+H Software Virtual CD
- Lightning UK ImgBurn
When using a CloneCD IMG file to create a disc, you must also supply the CCD and SUB files associated with the CloneCD IMG file.
Updated: January 8, 2021
2. Macintosh Disk Image
An IMG file is a disk image used to mount a file system. It can be mounted like a disk drive (e.g., an external hard drive), or an optical disc (e.g., a CD or DVD). IMG files are stored on the hard drive but are recognized as a disc or hard disk when mounted by the computer.
IMG files were used by Mac OS 9 and earlier versions of the Mac OS. They can still be opened on macOS, but they have been replaced by the newer .DMG disk image format.
NOTE: In some cases, renaming an IMG file's extension from ".img" to ".iso" allows other programs to open the file.
Updated: February 8, 2019
3. ERDAS IMAGINE Image File
Raster image created by ERDAS IMAGINE, a geospatial data authoring application; contains one or more layers, called bands, which include multiple image tiles that comprise the image; used to store small to very large geographical datasets.
IMG files may contain additional information, such as statistics, ground control points, map information, and image metadata. They also support subsampled raster layers, called pyramid layers, for faster screen display within GIS applications.
IMAGINE images use the ERDAS Hierarchal File Format (HFA) to store raster data.
Updated: October 12, 2010
4. Floppy Disk Image
An IMG file is a disk image created using the contents of a 3.5" floppy disk, which usually has a 1.44MB capacity. It stores a disk's contents as a single file that can be mounted on a computer virtually, instead of from the floppy drive. IMG files are often used to install and access older operating systems, such as MS-DOS, within virtual machines.
Floppy disk image files are not commonly used anymore since floppy disk drives are no longer included with most new computer systems.
You can view the contents of an IMG file using DiskCopy (Windows), and you can install an IMG-based operating system within a virtual machine using Oracle VM VirtualBox (cross-platform).
Updated: August 20, 2020
5. Garmin Map File
File used by Garmin GPS devices; contains map data, such as street names, navigation routes, and points of interest; used to store and upload user-customized and Garmin pre-installed map data onto Garmin devices.
Updated: May 30, 2010
6. GEM Image
Image file saved in the GEM format; contains a bitmap that allows monochrome, gray scale, and color images; originated from Digital Research, which is now owned by Novell.
GEM files were commonly used on older operating systems, but they are not used frequently any more.
Updated: December 31, 2015