Mac storage guides
Plain-English guides to Mac storage: System Data, purgeable space, Time Machine snapshots, iOS backups and Xcode data.
What is “System Data” on a Mac, and why is it so big?System Data is the catch-all category in macOS Storage. Here is what actually lives in it and how to see which part is yours to clear.Mac System Data is 100+ GB: how to find what is using itA step-by-step way to find the biggest contributors to a huge System Data bar on macOS, without deleting things you need.How to free up space on a Mac: what is safe and what is notA practical order of operations for reclaiming Mac disk space, starting with the safest and biggest wins.What is purgeable space on a Mac?Purgeable space is storage macOS can reclaim on demand. Here is what it contains and why it may not free up when you want it to.How to delete Time Machine local snapshots on a MacList and remove Time Machine local snapshots with Terminal to recover disk space. Commands, caveats and what to expect.iPhone and iPad backups taking space on your Mac: how to remove old onesFind, review and delete old iOS device backups stored on your Mac, using Finder rather than guessing at folders.Xcode Derived Data, simulators and device support: how to reclaim 20–60 GBSafe ways to clean Xcode’s Derived Data, unused simulators and device support files to get disk space back.Docker Desktop is using tens of GB on your Mac: how to reclaim itDocker keeps images, containers, volumes and build cache in one large disk image. Here is how to see what is reclaimable and clean it safely.Mac storage is full but you can’t find what is using itWhy Mac storage can look full with no obvious culprit, and a short list of places to check before you reach for any deletion.How to clear cache on a Mac safelyWhat Mac caches are, which ones are safe to clear, and how to do it per app without breaking anything.Cleaning Homebrew, npm and pip caches on a MacReclaim disk space from developer tool caches with the tools’ own cleanup commands, rather than deleting folders by hand.Optimize Mac Storage and iCloud Drive: free space without deleting filesHow Optimize Mac Storage and Remove Download work, and what to know before relying on them.