Windows
Compatible applications
Quick Facts
Basic information about this file format
Extension
.DMG
File Type
Apple Disk Image
Category
Archive
Best first step
Use compatible software
Quick Summary
A practical overview of the .dmg file format
A DMG file is an Apple Disk Image file, a common format used on macOS to distribute software. It's essentially a digital container that holds compressed software installers, applications, or other files. Think of it as a virtual disk drive. When you open a DMG file, macOS mounts it as a volume on y…
File extension
.DMG
File type
Apple Disk Image
Category
Archive
Recommended action
Open with a trusted compatible app
How to open a .dmg file
Start with a trusted app that supports this format
- Check the file extension carefully and confirm that the file name really ends with .dmg.
- 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- Update the application if the file was created by a newer version of the software.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 .dmg file?
File extension details and usage information
A DMG file is an Apple Disk Image file, a common format used on macOS to distribute software. It's essentially a digital container that holds compressed software installers, applications, or other files. Think of it as a virtual disk drive. When you open a DMG file, macOS mounts it as a volume on your desktop, allowing you to access its contents. This makes it easy to install applications or copy files to your computer. DMGs often include compression to reduce the file size for easier downloading and distribution. They can also be password-protected for security. The format supports various features like checksums to ensure data integrity and resource forks, which are specific to macOS. Once you've finished using the contents of a DMG file, you can unmount it, which removes the virtual disk from your desktop. DMGs are a standard way to distribute software and data on macOS, providing a convenient and secure method for packaging and delivering files.
Software Compatibility
Programs that may open or work with .dmg 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 .dmg files be converted?
Options for saving or exporting this file to another format
In many cases, a .dmg 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 .dmg file.
Why can't I open a .dmg file?
Common reasons this file type may not open correctly
Wrong software
The file may require a specific program that supports the .dmg 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 .dmg files
To open a .dmg file, use software that supports this file format.
- 7-Zip
- PeaZip
- HFSExplorer
- PowerISO
- UltraISO
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 .dmg 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.