Windows
Compatible applications
Quick Facts
Basic information about this file format
Extension
.QCOW2
File Type
QEMU Copy On Write version 2
Category
Data
Best first step
Use compatible software
Quick Summary
A practical overview of the .qcow2 file format
QCOW2 (QEMU Copy On Write version 2) is a disk image format used by QEMU, a popular open-source virtualization solution. It's designed to be a flexible and efficient way to store virtual machine disk images. Unlike raw disk images, QCOW2 images only allocate space on the host system as data is writ…
File extension
.QCOW2
File type
QEMU Copy On Write version 2
Category
Data
Recommended action
Open with a trusted compatible app
How to open a .qcow2 file
Start with a trusted app that supports this format
- Check the file extension carefully and confirm that the file name really ends with .qcow2.
- Use software that supports this file type. If one app does not work, try another compatible program for the same platform.
- Update the application if the file was created by a newer version of the software.
- Scan files from unknown sources before opening them, especially documents, archives, scripts, installers, and executable files.
What is a .qcow2 file?
File extension details and usage information
QCOW2 (QEMU Copy On Write version 2) is a disk image format used by QEMU, a popular open-source virtualization solution. It's designed to be a flexible and efficient way to store virtual machine disk images. Unlike raw disk images, QCOW2 images only allocate space on the host system as data is written to the virtual disk. This "copy-on-write" mechanism allows for smaller initial image sizes and efficient snapshotting. When a virtual machine writes to a sector on the virtual disk, the original data is preserved in a snapshot (if one exists), and the new data is written to the QCOW2 image. This allows for easy rollback to previous states. QCOW2 supports features like compression, encryption, and multiple backing files, making it a versatile choice for virtual machine storage. It is commonly used in cloud environments and by developers working with virtualized systems. The format is designed to be robust and handle large disk sizes, making it suitable for a wide range of virtual machine workloads. QCOW2 images are often used in conjunction with other virtualization technologies like KVM and Xen.
Software Compatibility
Programs that may open or work with .qcow2 files
macOS
Compatible applications
Linux
Compatible applications
Mobile
Mobile applications
No specific software is listed for this platform yet. Try checking the file source, identifying the original application, or using a trusted universal file viewer when appropriate.
Can .qcow2 files be converted?
Options for saving or exporting this file to another format
In many cases, a .qcow2 file can be converted by opening it in compatible software and using an option such as Save As, Export, or Convert. The available output formats depend on the file type and the application used.
- Use the original software that created the file when possible.
- Check whether the application supports exporting to common formats.
- Be careful with online converters when working with private, business, or sensitive files.
- If conversion fails, the file may be corrupted, incomplete, encrypted, or not actually a .qcow2 file.
Why can't I open a .qcow2 file?
Common reasons this file type may not open correctly
Wrong software
The file may require a specific program that supports the .qcow2 format.
Incorrect extension
The file extension may have been renamed manually, even though the actual file format is different.
Corrupted file
The file may be incomplete, damaged during download, or transferred incorrectly.
Outdated app
Your software may need to be updated before it can open newer versions of this file format.
Frequently Asked Questions
Common questions about .qcow2 files
To open a .qcow2 file, use software that supports this file format.
- QEMU
- VirtualBox
- 7-Zip (for extracting contents)
- WinImage (for mounting)
- qemu-img
Open the file in compatible software and look for options such as Save As, Export, or Convert. If no export option is available, the file may require a specialized converter or the original application that created it.
- Verify that the file extension is correct.
- Install or update compatible software.
- Try another application that supports this format.
- Check whether the file is corrupted, incomplete, or encrypted.
A file extension alone does not guarantee whether a file is safe or unsafe. Only open files from trusted sources, scan unknown files before opening them, and be especially careful with executable, script, archive, and document files.
File safety tips
Use caution with unknown files
Only open files from trusted sources. Before opening a .qcow2 file, scan it with antivirus software, verify that the file extension is expected, and avoid running unknown executable, installer, macro-enabled document, or script files.