How to view .img files?

.img is way too unspecific. This file extension is widely used for a variety of (raw) file formats. It is an abbreviation for “image” and that can be any image you can imagine—or cannot imagine at all, as you have never heard of it.

For example, .IMG used to be a GEM bitmap image file. Does anyone remember GEM at all? It was the Windows competitor from Digital Research. The Atari ST version was widely used, but there was also a DOS version of GEM. One of the stripped down versions (which was necessary to avoid copyright claims from Apple) was ViewMAX included in DR DOS 3.41, 5.0 and 6.0 as well as Novell DOS 7.0. It is now open source and can be downloaded freely as OpenGEM. Still requires DOS and is included in the FreeDOS distribution. For viewing GEM bitmap images, Windows programs of that time (around DOS-based Windows 3.0) such as Ventura Publisher could open and consequently convert such “GEM images” or “Atari ST images” into other, more widely used formats.

But I doubt that this kind of .img-file is what you meant. Still, you have to be more specific.

Most widely .img is used as a raw filesystem image of e.g. a floppy disk. As mentioned by others, such images can be opened by a number of programs. Or directly mounted under Unix-like systems like BSD and Linux. 7-Zip is also able to extract files from such images for supported filesystems, such as FAT. At least the command-line version. Just type 7z x image.img and it will extract the included files.

Note however that there are also other image formats out there, such as IBM's .dsk, sometimes using different file extensions. Such files can be raw floppy images, but they can also be in IBM's SAVEDSKF/LOADDSKF format. These files are basically raw files with stripped zeros at the end, but with a header at the beginning of the files. I doubt that 7-Zip can extract such images, even though it would only be necessary to find the appropriate offset. Anyhow, since the image past the header is basically raw and uncompressed, using dd you can extract the image and make it a raw .img floppy image. Suppose the header is hex:291 bytes long (which you will have to figure out by looking inside the file e.g. using a hex editor). This equals 657 bytes to skip, resulting in dd if=image.dsk of=rawimage.img bs=1 skip=657. The resulting rawimage.img would however be non-standard in size. This can be fixed, again, by using dd. dd if=/der/zero of=rawimage.img count=0 bs=1 seek=1474560 – this will make a sparse file out of it, resulting in the correct file size for a 1.44 MB floppy image and returning zeros at unused positions. Works with most programs under Linux.

But in general, .img can be any file that is classified as “an image”, thus any application can include a (proprietory) file with this extension. Such files can than only be used (opened) by said application.

If you want to open .img files, you can use 7-zip, which is freeware...

http://www.7-zip.org/

Once installed, right click on the relevant img file, hover over "7-zip", then click "Open Archive". Bear in mind, you need a seperate program, or Windows 7 to burn the image to disc!

Hope this helps!

Edit: Proof that it works (not my video, credit to howtodothe on YouTube).

you could use either PowerISO or WinRAR