If you are a developer using cloud virtualization, major providers offer official Windows 11 QCOW2-like images for KVM.

Google Cloud Image:

Microsoft’s own CBL-Mariner images – Not Windows 11 but related.

For most users, this is overkill, but it is the most official QCOW2 source available.

For users who require a pre-installed image (to save time on installation and updates), the most reputable community source is the GNS3 Vault or repositories maintained by well-known virtualization contributors.

The Best Current Repository Link: Grosscocoball Windows 11 Image Repository (Note: This link is often referenced in GNS3 forums and virtualization subreddits. If this specific link is down, the method below remains valid).

Alternative Reliable Source: GNS3 Official Download Page

Why these are considered "Best":

Risk Assessment:

Before diving into the links, it is important to understand why QCOW2 is the preferred format for QEMU/KVM virtualization (used by Proxmox, virt-manager, and OpenStack).

Unlike a raw disk image, QCOW2 supports:

If you don’t want to convert anything, the Cloudbase.it team provides ready-to-run Windows 11 QCOW2 images optimized for KVM.

Best link right now:
🔗 https://cloudbase.it/windows-cloud-image-download/

These images:

If you find a "Windows 11 Dev VM" on Microsoft's website (usually meant for Hyper-V), you can easily convert it to QCOW2.

Source: Microsoft Windows 11 Development Environment

Conversion Command: If you download the VHDX file, use qemu-img to convert it to the "Best" format for your needs:

qemu-img convert -f vhdx -O qcow2 Win11_Ent_VHDX.vhdx Win11_Final.qcow2

This is often the highest quality image you can get, as it comes directly from Microsoft, is fully patched, and includes developer tools.