Free online QCOW to QCOW2 converter
Convert legacy QCOW virtual disks to QCOW2 with qemu-img.
Convert QCOW to QCOW2 online - free
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How to convert qcow to qcow2 file
- Virtualization
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Source format overview
QCOW is an older QEMU Copy On Write virtual disk image format used by the QEMU emulator and related virtualization tools. It stores a virtual machine’s disk contents in a file and supports features such as sparse allocation and copy-on-write behavior, which helps save space compared with a fully preallocated disk image. QCOW files are typically found in older QEMU-based environments and legacy virtual machine setups.
Target format overview
QCOW2 is the newer and much more widely used successor to QCOW. It is also a QEMU virtual disk image format, but it adds important improvements such as snapshots, better metadata handling, encryption support in some workflows, and generally better compatibility with modern virtualization software. QCOW2 is the preferred format for most current QEMU/KVM deployments because it is more flexible and better supported.
How to perform the conversion
The most reliable way to convert .qcow to .qcow2 is with qemu-img, which is part of the QEMU tools package.
- Install QEMU tools if they are not already available. On Linux, this is often provided by a package such as
qemu-utilsorqemu-img. - Open a terminal or command prompt.
- Run the conversion command:
qemu-img convert -f qcow -O qcow2 input.qcow output.qcow2 - Verify the result with:
qemu-img info output.qcow2
If you are working in a virtualization manager, you may also be able to create a new QCOW2 image and copy the contents into it, but qemu-img convert is the standard and most direct method.
If you prefer a web-based workflow, you can convert the file on 101convert.com for free without installing any software.
Quality, compatibility, and limitations
The conversion is usually lossless because both formats are virtual disk containers, not compressed media formats. However, a few points matter:
- QCOW2 is not always identical in feature behavior to QCOW, so very old guests or tools may not fully support the newer image.
- Snapshots and backing files may require extra care. If the source image depends on a backing chain, make sure you convert the correct layer.
- Performance and size can change slightly after conversion because QCOW2 uses different metadata structures.
- Always keep a backup of the original image before converting, especially if it is attached to a running virtual machine.
In most cases, converting from QCOW to QCOW2 improves compatibility with modern QEMU and KVM environments while preserving the virtual disk contents.
Note: This qcow to qcow2 conversion record is incomplete, must be verified, and may contain inaccuracies. Please vote below whether you found this information helpful or not.
QCOW vs QCOW2: format comparison
How the QCOW and QCOW2 formats compare on the properties that matter most for this conversion.
| Property | .QCOW QEMU Copy On Write image | .QCOW2 QEMU Copy On Write version 2 |
|---|---|---|
| Compression | Both | Both |
| Encryption | Yes | Yes |
| Split archives | No | — |
| Bootable | Yes | Yes |
| Operating system support | Wide | Wide |
| Typical file size | Small | Medium |
| Open standard | Yes | No |
| Introduced | 2004 | 2004 |
| Developer | QEMU community / Fabrice Bellard | QEMU project / Fabrice Bellard and contributors |
Frequently asked questions
Is the QCOW to QCOW2 converter free?
Yes, converting QCOW to QCOW2 on 101convert.com is completely free. No registration, email address or installation is required.
How large can my QCOW file be?
You can upload QCOW files up to 2000 MB and convert up to 1 files at once in a single batch.
What happens to my uploaded files?
Files are processed automatically and deleted from our servers within a few minutes after conversion. We never view or share your files.
Do I need to install any software to convert QCOW to QCOW2?
No. The QCOW to QCOW2 conversion runs entirely online in your browser and works on Windows, Mac, Linux, Android and iPhone.
Did the conversion fail?
In most cases, the cause is an incorrect file format. Please upload a valid QCOW file for this QCOW to QCOW2 conversion. Occasionally, the issue may be on our side. We analyze recurring conversion failures and disable or fix the converter if we detect a defect.