Free online ISO to QCOW2 converter

Source format: ISO

ISO is a disc image format that stores the contents of an optical disc, usually a CD, DVD, or Blu-ray, in a single file. It is widely used for software distribution, operating system installers, recovery media, and archival copies of discs. An ISO image preserves the file structure of the disc, but it is not a virtual machine disk and does not contain a bootable hard drive layout by itself.

Target format: QCOW2

QCOW2 is a virtual disk format used mainly by QEMU and KVM virtualization environments. It supports features such as copy-on-write, snapshots, compression, and sparse allocation, which can save storage space and make it practical for virtual machines. QCOW2 is commonly used for Linux guests, test environments, and server virtualization.

How to perform the conversion

Important: ISO and QCOW2 are fundamentally different formats. An ISO is a disc image, while QCOW2 is a virtual hard disk. Because of that, there is usually no direct one-step conversion that turns an ISO into a meaningful QCOW2 disk image. In most cases, you either:

• create a new QCOW2 virtual disk and install the ISO contents into a virtual machine, or
• extract files from the ISO and copy them into a QCOW2 disk image if the ISO contains an operating system installer or a filesystem image.

Best practical method: install the ISO into a QCOW2 virtual machine

1. Create a new QCOW2 disk with qemu-img: qemu-img create -f qcow2 vm-disk.qcow2 20G
2. Start a virtual machine with the ISO attached as the boot media and the QCOW2 file as the hard disk. For example, with QEMU: qemu-system-x86_64 -m 4096 -cdrom installer.iso -hda vm-disk.qcow2 -boot d
3. Install the operating system from the ISO onto the QCOW2 disk inside the VM.
4. After installation, boot from the QCOW2 disk normally by removing the ISO from the virtual machine configuration.

If the ISO contains a filesystem image or files you want to preserve, you can extract its contents first and then place them into a QCOW2 disk image using a VM or disk utilities. On Linux, the ISO can be mounted read-only, for example: mount -o loop installer.iso /mnt/iso. Then create and attach a QCOW2 disk, partition it, format it, and copy the files into it.

Using desktop virtualization tools

In virt-manager, create a new virtual machine, choose the ISO as the installation media, and select QCOW2 as the disk format when creating the virtual disk. In File → New Virtual Machine, point to the ISO, then choose a new disk image in QCOW2 format. This is often the easiest method for users who want a graphical workflow.

Notes on quality, compatibility, and limitations

No direct file conversion exists in the usual sense because an ISO is not a hard disk image. If you simply rename an ISO to .qcow2, it will not work. The correct result depends on your goal: booting an operating system, preserving files, or creating a VM disk.

Bootability depends on the ISO. Some ISOs are bootable installers, while others are data discs. Even if the ISO boots in a VM, the QCOW2 disk must still be created and populated separately.

Compatibility is best with QEMU/KVM. QCOW2 is widely supported in Linux virtualization stacks, but some other hypervisors prefer different formats such as VMDK or VHDX. If you need to use the disk elsewhere, consider whether QCOW2 is the right target.

If you only need to work with the file online, you can convert the file on 101convert.com for free without installing any software, but for ISO to QCOW2 the practical outcome is usually a VM installation workflow rather than a literal format transform.