How do I open a .iso file?

On Windows use File Explorer (built in — right-click > Mount); on macOS use DiskImageMounter (built in); on Linux use Disk Image Mounter (built in). A byte-for-byte copy of a CD, DVD or installer disc in one file.

Can I convert a .iso file?

Yes. It is usually converted to .img, .dmg, .zip or .usb, either by exporting from one of the programs listed above or with a format converter.

.iso files

.iso file

ISO Disc Image

A byte-for-byte copy of a CD, DVD or installer disc in one file.

What opens a .iso file

Windows: File Explorer (built in — right-click > Mount), 7-Zip, Rufus (to write to USB)
macOS: DiskImageMounter (built in), Disk Utility (built in), balenaEtcher
Linux: Disk Image Mounter (built in), mount -o loop, balenaEtcher

What a .iso file is

An ISO holds an entire optical disc filesystem, which is why operating systems are distributed this way. Windows 10 and 11 mount one as a drive letter from the right-click menu, macOS mounts it on double-click, and Linux desktops offer Disk Image Mounter. To install from it you usually want to write it to a USB stick with Rufus, balenaEtcher or Startup Disk Creator rather than just copying the file across.

Converting it

A .iso file is commonly converted to .img, .dmg, .zip or .usb. It is a binary format, so a text editor will show unreadable characters rather than its contents.

Details

Extension: .iso
Full name: ISO Disc Image
Category: Disk images
MIME type: application/x-iso9660-image
Created by: ISO 9660 standard
Format: Binary

Common questions

How do I open a .iso file?: On Windows use File Explorer (built in — right-click > Mount); on macOS use DiskImageMounter (built in); on Linux use Disk Image Mounter (built in). A byte-for-byte copy of a CD, DVD or installer disc in one file.
What is a .iso file?: ISO Disc Image. An ISO holds an entire optical disc filesystem, which is why operating systems are distributed this way. Windows 10 and 11 mount one as a drive letter from the right-click menu, macOS mounts it on double-click, and Linux desktops offer Disk Image Mounter.
Can I convert a .iso file?: Yes. It is usually converted to .img, .dmg, .zip or .usb, either by exporting from one of the programs listed above or with a format converter.

.dmg — Apple Disk Image How Mac software is distributed — a disk image you mount and drag an app out of.
.vmdk — Virtual Machine Disk VMware's virtual hard disk — the contents of a whole virtual computer.
.cue — Cue Sheet A small text file describing the track layout of a .bin disc image.

Sources

Media Types Registry — IANA
Official vendor product documentation — At One Place

How these figures are compiled and checked