When your startup disk fills up, macOS starts struggling — apps stall, swap thrashes, and you get the dreaded "Your disk is almost full" warning. The good news is that most Macs are carrying tens of gigabytes of stuff that is genuinely safe to remove. This guide shows you how to free up space on Mac using only the tools already built in, then where a careful cleaner fits if you would rather not do it by hand.
Start with macOS Storage settings
Apple's own Storage panel is the right first stop, and it costs nothing.
- Open the Apple menu and choose System Settings.
- Go to General > Storage.
- Wait a few seconds for the colored bar to calculate. It breaks your disk down into Apps, Documents, System Data, macOS, and more.
- Click the small i icon next to any category to see what is inside it and remove individual items.
While you are here, turn on Apple's built-in recommendations: Store in iCloud, Optimize Storage (removes already-watched Apple TV downloads), and Empty Bin Automatically. These are safe, reversible toggles and a solid way to free up space on Mac without deleting anything important by hand.
Clear the obvious space hogs
Most of the easy wins come from four places. Work through them in order.
- Empty the Bin. Files you "deleted" still occupy the disk until the Bin is emptied. Right-click the Bin in the Dock and choose Empty Bin.
- Find large and old files. In Finder, press Cmd+F, set the search to This Mac, then add a rule for File Size is greater than 1 GB. Sort by size and review old installers, video exports, and disk images you no longer need.
- Clear the Downloads folder. It is a graveyard of
.dmgfiles and one-off attachments. Open~/Downloads, sort by size, and delete what you will not open again. - Uninstall apps you do not use. Drag an app from
/Applicationsto the Bin — but know that this leaves leftovers behind (more on that below).
Clear caches and temporary files
Caches are where "System Data" quietly grows. Each app keeps a working cache so it does not have to re-download or re-render things, but these can swell into many gigabytes over months.
To clear user caches manually:
- In Finder, choose Go > Go to Folder (or press Cmd+Shift+G).
- Type
~/Library/Cachesand press Return. - Open each app's folder and delete its contents — not the folder itself.
- Empty the Bin afterwards to actually reclaim the storage.
Two honest cautions. First, only clear user caches in ~/Library/Caches; leave the system-level /Library/Caches alone unless you know exactly what a folder is. Second, some "caches" are not disposable — a music app's offline downloads or Xcode's device-support files live in cache-like paths and are slow or impossible to recover. This is exactly the kind of judgement call that is easy to get wrong by hand.
Where MacScrub saves you the tedious parts
Everything above is free and worth doing. The catch is that the biggest remaining wins — duplicates and app leftovers — are genuinely tedious to chase manually.
MacScrub is a notarized, Apple-silicon-native cleaner built for exactly these slow jobs. It scans for the same junk you would hunt by hand, but with two safeguards that matter: every removal goes to the Trash first, so it is fully recoverable, and its cleaning rules are open source on GitHub — no telemetry, no trackers, no background daemons. Built-in guards skip things you would miss, like a music app's offline cache or your latest Xcode device support.
Here is how the manual route compares to letting MacScrub handle it:
| Task | Doing it by hand | With MacScrub |
|---|---|---|
| Clear app caches | Open each folder in ~/Library/Caches, judge what is safe | One scan, risky folders skipped by rules |
| Find duplicate files | No native tool; easy to delete the wrong copy | Byte-exact SHA-256 match, keeps one copy |
| Uninstall an app fully | Drag to Bin, then hunt prefs and support files | Removes the app plus all its leftovers |
| Recover a mistake | Gone if you deleted past the Bin | Everything lands in the Trash first |
The duplicate finder is the clearest example. macOS has no built-in way to find duplicate files, so people resort to eyeballing filenames — which is how the wrong copy gets deleted. MacScrub compares files by SHA-256 hash, so two files are only flagged as duplicates when their contents are byte-for-byte identical, then it keeps one and offers the rest for removal.
The full app uninstaller is the other big time-saver. Dragging an app to the Bin leaves its preferences, Application Support data, caches, and login items scattered across your ~/Library. MacScrub removes the app and its leftovers together, so you actually reclaim the storage instead of orphaning it.
A sensible cleaning routine
You do not need to do this often. A good rhythm for most people:
- Monthly: empty the Bin and clear your Downloads folder.
- Quarterly: review large and old files, and run a duplicate scan.
- As needed: fully uninstall apps the moment you stop using them, leftovers and all.
Do the free steps first — they cost nothing and clear real space. When you are tired of judging caches and chasing app leftovers, MacScrub is the faster, safer way to finish the job, and because it sends everything to the Trash first, an honest mistake is never permanent.