What is a .img file?
Raw Disk Image · Disk image · Various · n/a
An .img file is usually a raw, byte-for-byte copy of a disk or memory card, with no compression or extra structure. It is how operating-system images for devices like the Raspberry Pi are distributed.
What is a .img file used for?
Because a raw .img mirrors a disk exactly, it has no header of its own; its first bytes are whatever was on the disk (often a boot sector or partition table). This is why there is no single magic number.
You write an .img to an SD card or USB stick to clone the disk, using a tool like balenaEtcher or Raspberry Pi Imager. Some .img files are instead old floppy or CD images.
What opens a .img file?
The .img format opens in the following apps, grouped by operating system. If one app does not work, try another from the same list.
Windows
- balenaEtcher
- Rufus
- 7-Zip (some images)
macOS
- balenaEtcher
- Disk Utility
- dd
Linux
- balenaEtcher
- dd
- GNOME Disks
Open a .img file step by step
- Confirm the file really is a .img. Drop it into the WhatFileType identifier, which reads its signature in your browser without uploading anything.
- On Windows, open it with balenaEtcher or Rufus.
- On Mac, use balenaEtcher or Disk Utility.
- On Linux, try balenaEtcher or dd.
- Still stuck? Convert the .img to iso, which opens more widely.
Why can't I open my .img file?
Almost always because no installed app understands IMG. Install one of the apps above, or convert the file to a format your existing software already reads. If double-clicking opens the wrong program instead of nothing at all, the file association is set to the wrong app rather than the file being broken.
The other possibility is that the file is not really a .img at all. Drop it into the file identifier to check it by its bytes instead of its name. Nothing is uploaded.
How to convert a .img file
You can convert a .img file to iso, vhd, vmdk using a conversion tool or the export menu of an app that opens it.
IMG has no fixed magic number, so there is no signature table on this page. Its bytes alone do not prove the format: identification relies on the extension, the structure of the content and the program that created it. The magic-numbers reference lists the formats that do carry one.
Frequently asked questions
What is a .img file?
An .img file is usually a raw, byte-for-byte copy of a disk or memory card, with no compression or extra structure. It is how operating-system images for devices like the Raspberry Pi are distributed.
How do I open an .img file?
To write it to an SD card or USB, use balenaEtcher or Raspberry Pi Imager. To browse its files, mount it or open some images in 7-Zip.
What is the difference between IMG and ISO?
Both are disk images. ISO follows the optical-disc ISO 9660 standard; a raw .img is a plain byte copy of any disk, common for SD cards and drives.
How do I write an .img to an SD card?
Use balenaEtcher or Raspberry Pi Imager: select the .img, pick the card, and flash. This erases the card, so back it up first.
Related formats
Sources
Details on this page were checked against authoritative references. How sources are ranked and what is deliberately left out is set out in the methodology.