If you want to convert the DMG to a different compressed format (like ISO, which is much like the DMG file format for Windows), a tool like dmg2img will get the job done. But, if you need to get one open, 7-Zip has support for extracting DMGs. There’s not much reason you’d want to use DMG files in Windows since they usually contain macOS apps and not Windows apps. Next, delete the DMG file itself unless you have a reason for keeping it around. Clicking either one of these opens the DMG file.
The DMG mounts in two places: on your desktop and in the Finder sidebar under your hard drive. All you really need to do is double-click the DMG file to open it and mount it to your Mac. Well, luckily macOS does an excellent job of making everything easy. RELATED: Benchmarked: What's the Best File Compression Format? So How Do I Use DMG Files? Saving your data usage on downloads is always a good thing. And that’s second reason why macOS uses DMG files: they’re a compressed format (like a ZIP file) that makes your download smaller. This little window first goes through a phase of verifying the file, and then once it’s sure the file is good, moves on to decompressing it. This is what you see when the file is opening: DMG files include something called a checksum, which basically verifies that the file is 100% intact. The main reason macOS uses DMG files is to make sure the file downloaded properly and wasn’t tampered with.
