How to open a Mac DMG file in Windows

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The .dmg (disk image) suffix is ​​associated with Apple’s Disk Utility archive file format. Disk image files allow you to save files and create complete disk volumes that you can share with others.

Apple’s .dmg file can contain APFS or macOS Extended (HFS ) volumes, CD, DVD or Blu-Ray volumes, ISO9660 volumes (optical drives), or Microsoft FAT32 or extFAT volumes.

When creating disk images with the Disk Utility app included with macOS under /Applications/Utilities, you also have the option to password protect or encrypt image files.

You can also create blank .dmg files, double-click them in Finder to mount them on your desktop, and then copy files to them by dragging them onto the disk icon.

A disadvantage of .dmg files is that they are a proprietary Apple format. Most other operating systems, including Windows, cannot natively read and write .dmg files.

Thanks to third-party software and some freeware, you can do just that on Windows.

There are a number of free options for opening .dmg files on Windows 11, 10, 8 or 7. By far the easiest app for reading .dmg files on Windows is the excellent and free compression utility 7-Zip.

The 7-Zip utility works in Windows File Explorer. Once installed, all you have to do is install 7-Zip and then double-click a .dmg image in File Explorer to open it to access a .dmg file in Windows. A new window opens with the content of the .dmg file.

Alternatively, you can right-click a .dmg file in Windows and then select one of the three from 7-Zip’s submenu “Extract” Options to extract and copy the contents of a .dmg file to a location you specify in Windows File Explorer.

Another app for Windows that can extract files from .dmg files works very similarly to 7-Zip and is PeaZip. Once installed on Windows, the extraction process is similar to 7-Zip: just right-click a .dmg file in File Explorer and select one of the “Extract” Options from the pop-up menu. Choose a destination on your PC to save the files.

Another free alternative to 7-Zip on Windows is DMG Extractor (with a $10 paid version). The free version is limited to 4GB files, cannot extract from encrypted files, and can only extract five files at a time. The paid version removes these limitations and lets you browse the content of .dmg files directly.

Another free option is UltraDMG ($40 paid version). Although the Windows version of UltraDMG was primarily developed as a bootable disk image creator for macOS, it also allows you to extract the contents of .dmg files directly.

There is also the free DMGExtractor and HFSExplorer by Erik Larson (who also works on the Tuxera product mentioned below). They require a Java installation on Windows to work.

Another free option, if you’re a bit more tech-savvy, is to use the forensic software SleuthKit and its GUI front-end, Autopsy.

All the above apps are free or have limited free downloadable version along with paid versions.

Introduced decades ago, .iso files are an industry standard image format typically used for optical discs such as CDs and DVDs, but can also be used as a universal image format. Most modern operating systems, including macOS and Windows, can open .iso images natively, depending on the actual file system used in the .iso image.

Once you’ve converted a .dmg file to .iso, you can natively open the .iso file in Windows, provided the underlying file system of the .dmg file is one that Windows can read.

Apple’s Disk Utility can convert most .dmg files to .iso directly in macOS. To:

1. Open Apple’s Disk Utility from the Finder in macOS
2. Choose Images->Convert from the menu bar
3. In the opened files pane, select the .dmg file you want to convert and click on the .dmg file Choose Button
4. In the next save area, navigate to the destination where you want to save the converted file
5. If you want to encrypt the new disk image, select an encryption from the Encryption: Menu at the bottom right of the panel
6. Choose DVD/CD master of the “Image format:” pop-up menu in the lower-right corner of the pane
7. click”Convert”

Disk Utility will display a progress window detailing what it is doing during the conversion and whether the conversion was successful or not:

If successful, you now have a .cdr file in the destination you selected. Just rename the .cdr file extension to .iso and the conversion is complete. You can now copy the .iso file to your Windows computer.

You can also use the hdiutil command line tool in Terminal by following the instructions on this page. To learn more about hdiutil, type the following in the terminal:

man hdiutil and press To return.

If you want to do .dmg conversion on your Windows PC, you need to use third-party tools. Most third-party Windows tools are paid, with free limited download demos. The leading tools are:

There is also a free online .dmg converter called CloudConvert, but you need to sign up with email, google, twitter or facebook first. If you don’t have a fast internet connection, it may take some time to upload your .dmg images depending on the file size.

For example, some DVD images can be almost 8GB, some Blu-ray images up to 50GB.

UltraISO is simple and straight forward: install it, go to Tools->Convert and convert your .dmg file on Windows. It can also edit and extract disk images directly.

UltraISO supports all versions of Windows back to Windows 2000 – several decades value of Windows. It also has tiny system requirements: A Pentium 166MHz or higher (yes, MHz), only 64 MB of RAM and 10 MB of free disk space.

PowerISO is also simple and easy to use, offering direct conversion of .dmg files, as well as a variety of other disk-related options. It also provides back support for older versions of Windows Windows 98.

PowerISO offers a variety of options similar to UltraISO, including on-the-fly image editing, password protection, compression, direct image mounting, and audio format support and burning for compact discs. Both products also provide the ability to create bootable USB drives.

PowerISO also has the same low system requirements as UltraISO.

AnyBurn also offers easy one-button conversion of .dmg files, as well as a host of other disk-related features. It also supports a 32-bit version and Windows back to Windows 2000 and has the same minimum requirements as UltraISO and PowerISO.

TransMac is another similar .dmg disk utility for Windows and supports Windows back to Windows Vista. TransMac also offers some unique features like HFS+ formatting, splitting and compressing .dmg files, burning .dmg directly to CD/DVD/Blu-Ray and reading Mac multisession CDs (CDs with mixed volume formats or multiple volumes on a disc).

SysTools Disk Image Viewer Pro is last in our list of full-featured .dmg access apps for Windows, but with a steep price tag of $199 for a single-user license, it may be out of reach for some users. Nonetheless, SysTools Disk Image Viewer Pro has features that are on par with the rest.

Another option is to use the .rar file format as an intermediate format between .dmg and a format that Windows can understand (e.g. .iso).

Two paid utilities with free trials that do this are WinRAR ($30) and WinZip ($35).

Both products can convert .dmg files to .rar files, which can then be decompressed in Windows or exported to .iso format. There are three tiers of WinZip ranging from $30 to $100, and all WinZip versions include a Mac version.

Of course, macOS also knows how to read and write the .zip format with its built-in archive utility.

HFS for Windows ($19.95) and APFS for Windows ($49.95) are file system products for Windows that know how to mount and access Apple’s HFS+ and APFS volume formats respectively on Windows computers.

Paragon also has a similar product for macOS (Microsoft NTFS for Mac – $54.99) that does the opposite: it allows you to mount and access Microsoft Windows NTFS disks on your Mac desktop.

For home use only, Paragon has it all three products and a fourth product – Paragon CampTune – for the same $54.99 – an absolute steal. Paragon also offers APFS versions for Linux and Android.

If you use both the Paragon and Tuxera products, it’s easy picture your .dmg files onto a physical medium such as a USB stick, and then just plug the USB stick into your Windows computer – and vice versa from Windows to Mac (assuming you bought the third-party Mac products).

This may require an extra step, but makes accessing foreign file systems on other computers a breeze since no conversion needs to be done.

There are a few other free Windows apps that you can use to either access your .dmg files or convert them to formats Windows can understand, but they haven’t been updated in years and some are therefore only for 32-bit Operating systems or older versions suitable from macOS.

Two such utilities are Peter Wu’s dmg2img and dmg2iso.

There is an up-to-date GitHub page for dmg2iso, but you’ll have to build it yourself using the instructions listed. The page doesn’t make it clear whether the app itself has been updated for modern versions of macOS.

Also keep in mind that if you’re trying to open old .dmg, .smi, or .img files from Mac OS 9 or earlier from decades ago, those disk images may contain older Mac files that contain resource forks . Attempting to copy these files to a Windows PC without third-party HFS+ support installed may destroy the files’ resource forks, which may render the files unusable on older versions of macOS or Mac OS 9.

A guaranteed way to preserve resource forks in older Mac files is to copy them from a Mac hard drive to a macOS Extended (HFS+) .dmg and then open the .dmg as a read-only volume only.

When it comes to accessing your .dmg files on your Windows computers, you have many options – both free and paid. In a future article, we’ll explore how to create physical media to transport your files across platforms, regardless of disk format.