An ISO file is a sector-by-sector copy of an optical disc, named after the ISO 9660 file system standard for CD-ROMs. Modern ISOs often use the UDF file system for DVDs and Blu-ray discs.
ISO files are the standard way to distribute operating system installers such as Windows, Ubuntu and other Linux distributions, as well as software and archived discs. They can be mounted as a virtual drive, written to a USB stick to create bootable install media, or used directly in virtual machines like VirtualBox, VMware and Hyper-V.
| Extension | .iso |
|---|---|
| Full name | ISO Disc Image |
| Type | Disk images |
| Typical size | 700 MB (CD) to 4–8 GB (DVD/OS installers) |
How to open a .iso file
| Device | How to open it |
|---|---|
| Windows | Windows 8 and later mount ISO files natively in File Explorer; Rufus or the Media Creation Tool write bootable USB drives. |
| Mac | Double-clicking mounts most ISOs in Finder; balenaEtcher writes bootable USB drives. |
| iPhone / iPad | iPhones cannot mount or use ISO files; they can only store them in Files. |
| Android | Android cannot mount ISOs natively; ZArchiver can browse contents, and EtchDroid can write a bootable USB. |
| Linux | GNOME Disks, the mount command and Ventoy or dd handle ISO files. |
Converting .iso files
ISOs are usually written to USB rather than converted, using Rufus, balenaEtcher, Ventoy or the Windows Media Creation Tool. 7-Zip can extract an ISO's contents like an archive, and macOS hdiutil can convert ISO to DMG.
How to send a .iso file
- Open sendryo.com on the device that has the file and add it.
- Tap Get share code.
- On the other device, enter the code — the .iso file arrives directly, unchanged, at full quality.
Tips for sharing .iso files
- Download OS installer ISOs from the official vendor site and compare the published SHA-256 hash with /tools/checksum/ before use.
- ISOs are often several gigabytes; FAT32 USB drives cannot store files over 4 GB, so use exFAT or NTFS.
- A direct transfer between two computers on the same network is often faster than re-downloading a large ISO.
More: how to send iso files.
Frequently asked questions
How do I open an ISO file on Windows?
On Windows 8, 10 and 11, double-click the ISO or right-click and choose Mount. It appears as a virtual DVD drive in File Explorer. To create a bootable USB, use Rufus or Microsoft's Media Creation Tool.
How do I make a bootable USB from an ISO?
Use Rufus on Windows, balenaEtcher on Windows, Mac or Linux, or Ventoy to put several ISOs on one USB stick. Select the ISO and the USB drive and start writing. This erases everything on the USB drive.
Can I open an ISO file on a Mac?
Yes, double-click the ISO to mount it in Finder for most data discs. Some Windows installer ISOs use formats that mount only partially. To create a bootable USB from a Linux ISO, use balenaEtcher.
How do I send a large .iso file?
Open Sendryo on both devices, add the .iso file and share the 6-digit code. It goes directly to the other device at original quality, with no size limit set by us and no upload to a server.