Hyperspace is a new Mac application designed to save storage space. It merges data used by duplicate files, using a trick implemented by Apple in the Mac’s modern file system, giving you more storage space without any changes to your visible files.
Mac computers have used the Apple File System (also known as APFS) as the default file system since macOS 10.13 High Sierra, replacing the HFS+ system dating back to the 1990s, and APFS is now used on all modern Apple devices. One of its advantages is support for file clones, which allows the operating system to create copies of files without duplicating the entire contents in storage. When you duplicate a file in the Finder in macOS, it’s instant and doesn’t take up the entire storage space of the original file, because macOS using APFS cloning behind the scenes.
John Siracusa created Hyperspace as a tool to scan for files with the same content, even if they don’t have the same file names, and merge them together using APFS cloning. For example, if you have some applications that each have their own copies of resources (such as packaged libraries and runtimes), Hyperspace can mark them as file clones for macOS. The files still look like they’re in the same place in the filesystem, and your applications won’t notice the difference.
The blog post for Hyperspace explains, “Despite knowing about clone files since the APFS introduction nearly eight years ago, I didn’t give them much thought beyond the tiny thrill of knowing that I wasn’t eating any more disk space when I duplicated a large file in the Finder. But late last year, as my Mac’s disk slowly filled, I started to muse about how I might be able to get some disk space back. If I could find files that had the same content but were not clones of each other, I could convert them into clones that all shared a single instance of the data on disk.”
Hyperspace is a free download from the Mac App Store, and you can run it to see how much storage can be reclaimed. I ran it on my home folder on my M1 Mac Mini, which has been in constant use since 2022, and Hyperspace found 748MB of potential savings. You can run Hyperspace on any folder or drive, but it has to be an APFS-formatted volume. This won’t help you with a FAT32 flash stick or an old HFS+ Mac drive.
Importantly, Hyperspace isn’t a typical cleanup tool, as it won’t try to delete unused files. If you’re trying to figure out what is eating up all your Mac’s storage, you’ll still need to do some digging or use an app like DaisyDisk (the version on the site has more features than the Mac App Store version) or CleanMyMac. There’s also a basic file storage reporting tool available in the System Settings, if you navigate to General > Storage and click the information buttons on each menu listing.
Siracusa also explained some of the tool’s development in the blog post, saying, “I took an afternoon to whip up a Perl script (that called out to a command-line tool written in C and another written in Swift) to run against my disk to see how much space I might be able to save by doing this. It turned out to be a lot: dozens of gigabytes. At this point, there was no turning back. I had to make this into an app. […] By the end of that week, I’d written a barebones Mac app to do the same thing my Perl script was doing. In the months that followed, I polished and tested the app, and christened it Hyperspace.”
You can download Hyperspace for free from the Mac App Store for macOS 15.0 and higher. Reclaiming storage costs $10/month, $20/year, or the $50 lifetime unlock. The monthly and yearly options don’t renew automatically unless you explicitly choose the subscription option.
Source: Hypercritical via John Siracusa (Mastodon)
