Quick answer: CleanMyMac is worth it if you want one app that cleans, watches for malware, updates your apps and tidies startup items, and you’re happy with a subscription. If your only problem is a full disk, it’s more app than you need. Start with what macOS gives you for free, then use a disk map like Free Mac to see where the space went before you delete anything.

“Should I buy CleanMyMac?” is one of the most searched Mac questions there is, and most answers are either an ad or a rant. This one is neither. I went through what it does, job by job, and checked each one against what’s already on a Mac in 2027.

For context, the Mac I tested on is a MacBook Air with 245 GB of storage and, on the day I measured, 5.3 GB free. So the “disk full” warning is not theoretical for me.

What CleanMyMac does

CleanMyMac is made by MacPaw and has been around for well over a decade. It’s notarized by Apple and it’s a real, polished app. Its main jobs are:

• Cleanup: finds caches, logs, language files and other leftovers to remove.
• Protection: scans for malware and adware.
• Performance: manages login items and background apps, and runs maintenance tasks.
• Applications: uninstalls apps with their leftover files and updates the ones you keep.
• Space Lens: a visual map of what’s using your disk.

Those are all useful jobs. The question is how many of them you’d otherwise get for free.

Job by job: CleanMyMac vs what’s already on your Mac

1. Cleaning caches and junk

Built in: partly. System Settings, General, Storage gives recommendations (empty Trash automatically, review large files, optimise storage). It does not clear app caches.

By hand: in Finder press Shift, Command and G, go to ~/Library/Caches, quit your apps and empty the biggest folders. On my Mac that folder was 10 GB, and 6.3 GB of it was one browser.

Verdict: a cleaner saves you ten minutes here. It doesn’t find space you couldn’t find yourself.

2. Malware protection

Built in: yes. macOS has XProtect, which checks apps against known malware and updates in the background, and Gatekeeper, which blocks unsigned apps.

Verdict: for most people, macOS plus sensible downloading is enough. A second scanner is reassurance more than necessity.

3. Login items and background apps

Built in: yes. System Settings, General, Login Items and Extensions lists everything that opens at startup or runs in the background, with a switch for each.

Verdict: free, and two minutes of your time.

4. Uninstalling apps completely

Built in: no. Dragging an app to the Trash removes the app but leaves its settings, caches and support files in your Library folder. Some of those are hundreds of megabytes. Free Mac’s guide on why uninstalling Mac apps leaves files behind shows where they hide.

Verdict: this is a real gap, and any good tool should cover it.

5. Updating apps

Built in: the App Store updates its own apps, and most other apps update themselves.

Verdict: nice to have in one place, rarely essential.

6. Seeing what’s using the space

Built in: barely. The Storage bar lumps a huge amount into “System Data” and “Documents” with no way to look inside. This is what Storage settings can and can’t tell you.

Verdict: this is the job that matters most when the disk is full, and it’s the one macOS does worst.

So, is it worth it?

Worth it if you want one app to do all six jobs, you like a guided “click Scan and you’re done” experience, and a subscription doesn’t bother you.

Skip it if your problem is “my disk is full and I don’t know why”. Four of the six jobs are free in macOS, and the two that aren’t (finding the space and removing app leftovers) can be done by a lighter tool.

The lighter option for a full disk: Free Mac

Free Mac does one thing and does it thoroughly: it shows you where your space went. It scans the drive and draws every folder as a box sized by the space it uses, so the biggest problem is the biggest block on screen.

It marks which folders are safe to clear, like caches, old iPhone backups and developer build folders, and it shows what Finder hides. Anything you clean goes to the Trash first, so nothing vanishes by accident.

Its Apps view lists every app with the space it uses, including the leftovers that dragging to the Trash would miss.

Scanning and the map are free, with no account and no trial timer. A paid key unlocks exact sizes and cleaning. If Space Lens is the part of CleanMyMac you’d use, start here.

What to do today, in order

1. Empty the Trash and turn on “Remove items from the Trash after 30 days” in Finder settings.
2. Go through System Settings, General, Storage and accept the recommendations you agree with.
3. Check Login Items and Extensions and switch off what you don’t need.
4. Run a free scan to see the big folders. If you’re short on space after a macOS update, read disk full after a macOS update first.
5. Only then decide whether you want an all in one cleaner. Many people find they don’t.

If you want the full list of options side by side, Free Mac keeps a page of CleanMyMac alternatives. And I wrote about the storage settings that look helpful but aren’t in I Gave macOS Storage Settings a Real Chance.

Do you pay for a Mac cleaner? Was it worth it for you? I’d like to hear in the comments.

Quick answer: empty the Trash, open System Settings, General, Storage and work through its recommendations, clear old downloads and installers, then remove caches, old iPhone backups and leftovers from apps you’ve deleted. Before deleting anything big, see where the space is: Free Mac’s free scan draws your whole drive as a map.

My MacBook Air has 245 GB and, as I write this, 5.3 GB free. These are the steps I use on it, in order, and the rule behind them is simple: start with things that can’t hurt you, finish with things you should check first.

1. Empty the Trash

Files in the Trash still take space. Empty it, and in Finder, choose Finder, Settings, Advanced and tick Remove items from the Trash after 30 days so it never piles up again.

2. Use Storage settings’ recommendations

Open System Settings, General, Storage. At the top you’ll see recommendations such as Store in iCloud, Optimise Storage (removes watched Apple TV films and shows) and Empty Trash Automatically. Turn on the ones that suit you.

Below that, click the info button next to a category to review it. It’s a good start, though it lumps a lot into System Data. I gave it a fair go in I Gave macOS Storage Settings a Real Chance.

3. See where the space is going

Before you go hunting, look at the whole drive once. A map of every folder sized by the space it takes shows you in a minute what would take an hour in Finder.

Free Mac’s scan is free, and it marks which folders are safe to clear.

4. Clear Downloads and old installers

Open Downloads, sort by size, and remove .dmg and .pkg installers for apps you’ve already installed, plus anything you’ve already filed elsewhere. Free Mac’s guide to the Downloads folder taking up space covers the usual suspects.

5. Clear big caches

My user caches came to 10 GB, and 6.3 GB of that was Chrome. Quit your apps, go to ~/Library/Caches with Shift, Command and G in Finder, and empty the contents of the biggest folders. Clear browser caches from inside each browser. The browser by browser version is in Chrome Was Using 6.2 GB of Cache on My Mac.

6. Delete old iPhone and iPad backups

Backups made through Finder can run to tens of gigabytes each. Connect any device, select it in Finder, click Manage Backups, and delete the ones for devices you no longer have.

7. Remove apps you don’t use, properly

In Finder’s Applications folder, switch to list view and add the Date Last Opened column to find apps you haven’t touched in months. Then remove each one together with its leftovers: an app’s support files and caches can be far bigger than the app.

More in why uninstalling Mac apps leaves files behind.

8. Clear developer folders (if you write code)

node_modules folders, package caches, Xcode build data and simulators grow without telling you. They rebuild when needed, so old projects are safe targets. I measured mine in Developer Folders Took 29 GB of My MacBook Air.

9. Move big media off the Mac

Large video projects, old photo libraries and music you rarely play can live on an external drive or in iCloud. In Photos, turn on Optimise Mac Storage in Settings, iCloud to keep smaller copies on the Mac.

10. Look inside System Data last

System Data mixes things you should keep with caches, logs and old backups you shouldn’t need. Leave it until last, and only remove what you can identify. Free Mac’s guide System Data explained walks through it.

What not to delete

• Anything inside the System folder.
• Your whole Library folder or the Caches folder itself (empty folders inside it, not the folder).
• Photos or Music library files from Finder. Clean those from inside the app.

Why people use Free Mac for this

• Scanning is free. Scan the whole Mac or one folder, see the map and every list, with no account and no trial timer.
• It shows what Finder hides: caches, app leftovers, build folders and old disk images, drawn as one map where the biggest block is the biggest problem.
• It says what’s safe. Each app’s real footprint is shown with its leftovers, and developer folders are marked when they rebuild themselves.
• Nothing is deleted outright. Cleaning moves files to the Trash, so you can put anything back.
• A subscription key unlocks cleaning, and it only asks at the moment you clean. It runs on macOS 10.15 or later.

Find your biggest block first with the free scan at free-mac.online.

People also ask

Why is my Mac storage full when I don’t have many files?

Most of the space usually isn’t in your files. It’s in caches, app data, iPhone backups and developer folders made of thousands of small files. A scan of the whole drive shows them.

How do I free up space on my Mac without deleting files?

Store files in iCloud with Optimise Mac Storage, move big media to an external drive, and clear caches, which apps rebuild on their own.

Is it safe to delete System Data on a Mac?

Parts of it, yes: old caches, logs and backups. Never delete system files, and only remove what you can identify.

How much free space should a Mac have?

Aim for at least 10 to 15 percent of the drive free. macOS needs room for updates, swap and temporary files.

The warning tells you there’s a problem. It never tells you where. These are the questions I kept asking my own Mac, and the tools that finally answered them.

My MacBook Air has a 245 GB drive. Today it has 5.3 GB free, and macOS has told me so more than once, always in the same polite tone, never with a single useful detail.

So I started a list. Every time I asked my Mac a simple question about its own storage and got no answer, it went on the list. These are eight of them, with what macOS gives you, what answers it, and the catch.

1. “Which folder is using all the space?”

What macOS gives you: Storage settings shows a coloured bar split into Apps, Documents, Photos and System Data. It never names a folder. Finder can tell you a folder’s size, one Get Info window at a time.

What answers it: Free Mac scans the whole drive and draws it as a map. Every folder is a box sized by the space it takes, so the biggest problem is the biggest box. It also says which items are safe to remove.

The catch: the scan and the map are free; a subscription key unlocks cleaning, and it only asks when you clean. Anything you clean goes to the Trash first.

2. “What on earth is System Data?”

What macOS gives you: a grey bar, sometimes 40 GB or more, that you can’t click into.

What answers it: Free Mac’s map shows the caches, logs, old backups and app data that macOS lumps into System Data, folder by folder. Free Mac’s guide System Data explained lists what usually hides in it.

The catch: some of it is genuinely macOS and should stay. The point is knowing which part is which.

3. “How much space does this app really take?”

What macOS gives you: the size of the app itself. Chrome on one Mac, for example, is 1.4 GB in Applications.

What answers it: Free Mac’s Apps view adds up an app with everything it keeps elsewhere. That same Chrome held 11 GB more in support files and caches, for a real footprint of 13 GB.

The catch: for an app you use every day, a lot of that comes back. It matters most for apps you’ve stopped using. AppCleaner is a free alternative if you only want to remove apps.

4. “What did that app leave behind when I deleted it?”

What macOS gives you: nothing. Drag an app to the Trash and its settings, caches and support files stay in your Library folder.

What answers it: Free Mac lists each app with its leftovers, so you can remove them together. The full walk through is in I Uninstalled Mac Apps by Dragging Them to the Trash for Years.

The catch: check the list before you confirm. Shared folders occasionally match more than one app.

5. “Which apps haven’t I opened in months?”

What macOS gives you: this one is hidden but built in. Open Applications in Finder, switch to list view, choose View, Show View Options and tick Date Last Opened. Sort by it.

The catch: apps that run in the background, such as menu bar tools, can look unused when they aren’t.

6. “How big is every folder in this list?”

What macOS gives you: Finder’s list view shows “ — “ for folder sizes by default. Choose View, Show View Options and tick Calculate all sizes, then sort by Size.

The catch: it’s slow on big folders, and it skips hidden ones like your Library.

7. “Do I have the same files twice?”

What macOS gives you: Photos can find duplicate photos in its own library. Nothing does it for the rest of the disk.

What answers it: dupeGuru is a free, open source duplicate finder, and Gemini 2 is a polished paid one. Both compare what’s inside the files, so renamed copies are caught too.

The catch: review before deleting. Two copies of a file in two projects can both be needed.

8. “Why did Xcode take 40 GB?”

What macOS gives you: nothing at all. Xcode keeps build data, simulators and device support files in folders most people never see.

What answers it: DevCleaner for Xcode is a free app that lists those folders and clears the ones you choose. Free Mac’s Dev view also marks developer folders that rebuild themselves, and its guide to cleaning Xcode Derived Data covers it by hand.

The catch: the next build takes longer, because Xcode rebuilds what you deleted.

Why people use Free Mac for this

• Scanning is free. Scan the whole Mac or one folder, see the map and every list, with no account and no trial timer.
• It shows what Finder hides: caches, app leftovers, build folders and old disk images, drawn as one map where the biggest block is the biggest problem.
• It says what’s safe. Each app’s real footprint is shown with its leftovers, and developer folders are marked when they rebuild themselves.
• Nothing is deleted outright. Cleaning moves files to the Trash, so you can put anything back.
• A subscription key unlocks cleaning, and it only asks at the moment you clean. It runs on macOS 10.15 or later.

Get answers to the first four questions in one scan: try Free Mac’s free scan.

That’s my list. What does your Mac refuse to tell you about its storage? Put it in the comments and I’ll test the answers for the next one.

Quick answer: purgeable space is data macOS is allowed to delete on its own when it needs room: local Time Machine snapshots, iCloud files that are also in the cloud, and some caches. You can see it in Finder by selecting your drive and choosing File, Get Info. macOS frees it automatically when you run low, but you can speed that up by deleting local snapshots and letting iCloud remove downloaded copies. If there’s little purgeable space and your drive is still full, the space is genuinely in use, and Free Mac’s free scan shows where.

What purgeable space is

macOS sorts some of what’s on your drive as “it’s here, but I can throw it away if I have to”. That pile is purgeable space. It’s usually made of:

• Local Time Machine snapshots that macOS keeps between backups.
• iCloud Drive and Photos files that are safely in iCloud and also downloaded to the Mac.
• Some caches, such as streamed music and video macOS can download again.

Because macOS can remove it at any time, it counts the space as available. That’s why Storage settings and Finder can show different numbers for free space.

How to see your purgeable space

1. Open a Finder window and select your drive (usually Macintosh HD) in the sidebar, or click the desktop and choose Go, Computer.
2. Choose File, Get Info.
3. Look at Available. If part of it is purgeable, Finder says so in brackets.

What I found on my own Mac

I measured my MacBook Air today without changing anything. The drive is 245 GB. macOS reported 5.3 GB available, and 5.4 GB available for important use, which is the figure that includes purgeable space. So purgeable space was about 0.1 GB, and there were no local snapshots at all.

That’s worth knowing. A lot of guides treat purgeable space as the hidden answer to a full disk. On a Mac that’s genuinely full, macOS has often purged it already. If your numbers look like mine, stop hunting for purgeable space and look at what’s using the drive.

How to free purgeable space yourself

1. Delete local Time Machine snapshots

Open Terminal and list them first, which changes nothing:

tmutil listlocalsnapshots /

If any are listed, delete one by its date with tmutil deletelocalsnapshots followed by the date shown, or connect your backup drive and let Time Machine finish a backup, which tidies them up on its own.

2. Let iCloud remove downloaded copies

Turn on Optimise Mac Storage in System Settings, your name, iCloud, iCloud Drive. For files you need offline less often, right click them in Finder and choose Remove Download. The file stays in iCloud and its icon shows a small cloud.

3. Empty the Trash and restart

Files in the Trash aren’t purgeable; they’re just waiting. Empty it, then restart so macOS can tidy temporary data.

4. Make a big file and delete it (not recommended)

Some guides suggest filling the drive with a huge file to force macOS to purge. It works, but on a nearly full Mac it can leave you with no space at all for a moment. There are safer ways above.

When purgeable space isn’t the problem

If Get Info shows little purgeable space, the space is in real files. On full Macs it’s usually in caches, iPhone backups, developer folders, leftovers from deleted apps and the grey “System Data” bar.

Free Mac’s guide to purgeable space on a Mac has more on the snapshot commands, and System Data explained covers what hides in that grey bar. I also measured where every gigabyte went on this same Mac in My MacBook Air Had 6 GB Free.

Why people use Free Mac for this

• Scanning is free. Scan the whole Mac or one folder, see the map and every list, with no account and no trial timer.
• It shows what Finder hides: caches, app leftovers, build folders and old disk images, drawn as one map where the biggest block is the biggest problem.
• It says what’s safe. Each app’s real footprint is shown with its leftovers, and developer folders are marked when they rebuild themselves.
• Nothing is deleted outright. Cleaning moves files to the Trash, so you can put anything back.
• A subscription key unlocks cleaning, and it only asks at the moment you clean. It runs on macOS 10.15 or later.

See what’s using your drive with the free scan at free-mac.online.

People also ask

Is it safe to delete purgeable space on a Mac?

Yes. macOS only marks data as purgeable when it can remove it without losing anything you need, such as files already safe in iCloud or snapshots between backups.

Why is my purgeable space not going away?

macOS only purges when it needs the room, so it may sit there for days. Deleting local snapshots or turning on Optimise Mac Storage frees it sooner.

Does purgeable space count as free space?

Mostly, yes. macOS counts it as available because it can clear it on demand, which is why different windows show different free space figures.

How do I check purgeable space in Terminal?

Run tmutil listlocalsnapshots / to see snapshots, the most common purgeable item. Finder's Get Info window shows the total.

Quick answer: quit your apps, open Finder, press Shift, Command and G, type ~/Library/Caches and delete the contents of the folders that are biggest, never the Caches folder itself. Clear browser caches from inside each browser. For developer caches, use the tool’s own clean command. To see which caches are big before you touch anything, Free Mac’s free scan draws them on one map.

I checked my own MacBook Air today. It has a 245 GB drive with 5.3 GB free, and its user cache folder alone was 10 GB. Most of it came from five places:

• Google (Chrome): 6.3 GB
• Yarn: 1 GB of downloaded JavaScript packages
• An app updater’s download folder: 878 MB of an update that had already been installed
• Playwright: 539 MB of test browsers
• pnpm: 334 MB

The system wide cache folder, by comparison, held 12 KB. On most Macs the space is in your own user caches, not in macOS.

What a cache is, and why deleting one is usually safe

A cache is a copy an app keeps so it doesn’t have to download or work something out again: thumbnails, web pages, packages, map tiles. Delete it and the app rebuilds what it needs the next time it runs. That’s why it’s safe, and also why it comes back.

The rule of thumb: clear a cache when it’s big and you no longer use the app much, or when an app is misbehaving. Clearing everything every week gains little, because it fills up again.

1. Clear user caches (the big one)

1. Quit every app you can.
2. In Finder, press Shift, Command and G, type ~/Library/Caches and press Return.
3. Switch to list view, then choose View, Show View Options and tick Calculate all sizes so you can sort by size.
4. Open the biggest folders and move their contents to the Trash. Leave the folders themselves in place.
5. Restart, then empty the Trash.

Free Mac’s guide to Library Caches on a Mac goes folder by folder if you want more detail.

2. Clear browser caches

Use the browser’s own setting rather than deleting files by hand, so it doesn’t trip over itself:

• Chrome: Settings, Privacy and security, Delete browsing data, tick only Cached images and files.
• Safari: Settings, Advanced, tick Show features for web developers, then choose Develop, Empty Caches (Option, Command and E).
• Firefox: Settings, Privacy and Security, Cookies and Site Data, Clear Data, tick only cached web content.

Chrome was the biggest single cache on my Mac. I went through every browser in detail in Chrome Was Using 6.2 GB of Cache on My Mac, and Free Mac has a guide to Chrome taking up space.

3. Clear developer caches with their own commands

If you write code, package managers keep huge caches. Their own commands clear them cleanly:

• npm: npm cache clean --force
• Yarn: yarn cache clean
• pnpm: pnpm store prune (removes packages no project uses)
• Homebrew: brew cleanup

Everything comes back the next time a project installs, so this is best for tools you’ve stopped using. More on Yarn and pnpm stores taking up space.

4. Clear leftover update downloads

Some apps download their updates into a cache folder and never clean it up. On my Mac one updater folder still held 878 MB after the update had gone in. Look for folders in ~/Library/Caches named after an app with ShipIt or Updates in the name, quit that app, and empty them.

5. System caches: mostly leave them alone

The system cache folder at /Library/Caches is usually small and macOS manages it. Restarting your Mac clears a lot of temporary data on its own. Don’t delete anything inside the System folder.

Which caches aren’t worth clearing

• Apps you use every day. Their caches refill within a day and the app runs slower while it rebuilds.
• Photos and Music. Their caches are part of the library; clear them from inside the app, not in Finder.
• Anything you can’t identify. If a folder name means nothing to you, look it up first.

Not sure what else is safe? This guide on what is safe to delete on a Mac covers the common folders.

Why people use Free Mac for this

• Scanning is free. Scan the whole Mac or one folder, see the map and every list, with no account and no trial timer.
• It shows what Finder hides: caches, app leftovers, build folders and old disk images, drawn as one map where the biggest block is the biggest problem.
• It says what’s safe. Each app’s real footprint is shown with its leftovers, and developer folders are marked when they rebuild themselves.
• Nothing is deleted outright. Cleaning moves files to the Trash, so you can put anything back.
• A subscription key unlocks cleaning, and it only asks at the moment you clean. It runs on macOS 10.15 or later.

Start with the free scan at free-mac.online and see which cache is the big one on your Mac.

People also ask

Is it safe to delete everything in ~/Library/Caches?

Deleting the contents with your apps closed is generally safe, because apps rebuild their caches. Delete what’s inside the folders, not the Caches folder itself, and restart afterwards.

Will clearing cache make my Mac faster?

Not really. It frees space, and it can fix an app that’s acting up, but apps often run a little slower for a while as they rebuild. If your Mac is slow, a nearly full drive is a likelier cause than the cache itself.

How often should I clear cache on a Mac?

Only when a cache is big or an app misbehaves. A monthly look at the biggest folders is plenty.

Does restarting a Mac clear the cache?

A restart clears temporary files and some system caches, but not the app caches in your Library folder.

Quick answer: Mac storage usually fills up on its own because of caches, iPhone backups, Time Machine snapshots, swap, app data and, if you write code, developer folders. None of them show up as files you made. Find which one is growing on your Mac with the free scan in Free Mac, then fix that one.

My MacBook Air sits at 6 to 7 GB free on a 228 GB drive, and it never had many photos or videos. When I measured it, the space was in things that grow by themselves: 11 GB of caches, about 29 GB of developer folders, 10 GB of hidden system files.

1. Caches grow every day

Browsers and apps keep copies of everything to load faster. Mine were 11 GB, 6.2 GB from one browser. Fix: clear the biggest ones from inside each app. See what’s safe in Library/Caches.

2. iPhone and iPad backups

Each local backup can be tens of gigabytes, and old ones stay. Fix: delete old backups in Finder under your device’s Manage Backups. Guide: iPhone backups taking up space.

3. Time Machine snapshots

When your backup drive isn’t connected, macOS keeps local snapshots on the Mac. Fix: connect the backup drive so they move off. More in Time Machine taking up space.

4. Swap and temporary files

When memory is busy, macOS writes to disk. My /private/var held 10 GB, 2 GB of it swap. Fix: restart, which clears most of it. I covered it here: The Mac Storage You Can’t See.

5. Developer folders

node_modules, package caches and toolchains grow with every project. Mine were about 29 GB. Fix: clear rebuildable folders for projects you’re not working on: Developer Folders Took 29 GB of My MacBook Air.

6. App data and AI tools

Apps store models, libraries and history in Application Support. Mine was 8.5 GB, one app taking 2.5 GB. Fix: check the biggest folders and remove data for apps you no longer use.

7. Leftovers from deleted apps

Dragging apps to the Trash leaves their data behind. I found about 2 GB from apps I’d already removed. Fix: uninstall properly, leftovers included.

8. iCloud downloads and Photos

Opening iCloud files and photos downloads full copies. Fix: turn on Optimise Mac Storage in Photos and iCloud Drive settings so originals live in iCloud.

9. Downloads and old installers

Disk images and installers stay after you’ve used them. Mine was only 2.2 GB, but on many Macs it’s the biggest single folder. Fix: sort Downloads by size and clear what you’ve installed.

Why people use Free Mac for this

• Scanning is free. Scan the whole Mac or one folder, see the map and every list, with no account and no trial timer.
• It shows what Finder hides: caches, app leftovers, build folders and old disk images, drawn as one map where the biggest block is the biggest problem.
• It says what’s safe. Each app’s real footprint is shown with its leftovers, and developer folders are marked when they rebuild themselves.
• Nothing is deleted outright. Cleaning moves files to the Trash, so you can put anything back.
• A subscription key unlocks cleaning, and it only asks at the moment you clean. It runs on macOS 10.15 or later.

Run the free scan from free-mac.online and see your own numbers first.

How to stop it happening again

1. Scan once a month and look at what grew.
2. Keep 15 to 20 percent free. macOS needs room for swap and updates.
3. Clear the biggest grower first, not everything at once.

The full list of causes is in why does my Mac fill up so fast.

People also ask

Why does my Mac storage keep filling up by itself?

Caches, snapshots, swap and backups grow in the background without you saving anything.

Why is System Data so large on my Mac?

It’s a catch all for caches, logs, snapshots and temporary files. Where all 222 GB went on mine: I Measured Where It Went.

How much free space should a Mac have?

Aim for 15 to 20 percent of the drive, so macOS has room to work and update.

Quick answer: in your user Library, Caches, Logs and leftovers from apps you’ve already uninstalled are generally safe to delete. Preferences, Keychains, Mail, Messages and the Application Support and Containers folders of apps you still use are not. Never touch /System/Library. To see which Library folders are big before you touch anything, run the free scan in Free Mac.

How to open the Library folder

1. In Finder, hold Option and open the Go menu. Library appears in the list.
2. Or press Command, Shift and G and type ~/Library.

There are three Library folders: yours (~/Library), the Mac’s (/Library) and the system’s (/System/Library). This guide is about yours.

What I found in mine

• Library total: 23 GB.
• Caches: 11 GB.
• Application Support: 8.5 GB.
• Containers: 11 MB. Logs: 10 MB.

Safe to delete

Caches

Copies apps keep to load faster. They rebuild as you use the app. Clear one app’s cache at a time with that app closed, rather than the whole folder. Mine held 6.2 GB from one browser alone: Chrome Was Using 6.2 GB of Cache on My Mac. Guide: what’s safe in Library/Caches.

Logs

Records apps write while they run. Safe to clear, usually small.

Leftovers from uninstalled apps

Folders in Application Support, Caches, Containers and Preferences named after apps you no longer have. On my Mac, 11 such folders over 50 MB added up to about 2 GB. How to find them: I Uninstalled Mac Apps by Dragging Them to the Trash for Years.

Saved Application State

Window positions apps restore at launch. Safe to clear; apps just open fresh.

Be careful

Application Support

Real app data: libraries, downloaded content, projects. Only delete folders of apps you’ve removed.

Containers and Group Containers

Data for App Store and sandboxed apps, including documents. Leave them for apps you use. More: Library Containers taking up space.

Never delete

• Preferences: apps lose their settings or misbehave.
• Keychains: your saved passwords.
• Mail and Messages: your email and chat history.
• Mobile Documents: your iCloud Drive files.
• Anything in /System/Library: macOS protects it and needs it.

The full table is in is it safe to delete Library folders.

Why people use Free Mac for this

• Scanning is free. Scan the whole Mac or one folder, see the map and every list, with no account and no trial timer.
• It shows what Finder hides: caches, app leftovers, build folders and old disk images, drawn as one map where the biggest block is the biggest problem.
• It says what’s safe. Each app’s real footprint is shown with its leftovers, and developer folders are marked when they rebuild themselves.
• Nothing is deleted outright. Cleaning moves files to the Trash, so you can put anything back.
• A subscription key unlocks cleaning, and it only asks at the moment you clean. It runs on macOS 10.15 or later.

Run the free scan from free-mac.online and see your own numbers first.

People also ask

Can I delete the whole Library Caches folder?

It’s safer to clear one app at a time with the app closed. Deleting everything at once can make apps slow to start or lose state.

Why is my Library folder so big?

Usually caches and app data growing over years, plus leftovers from apps you removed.

Will deleting Library files break my Mac?

Not if you stick to caches, logs and leftovers of removed apps. Leave Preferences, Keychains and system folders alone.

Quick answer: open System Settings, General, Storage and click the info button next to Documents to see your largest files, or search in Finder with Command and F and filter by File Size. Then look at folders, not just files: most lost space hides in folders full of small files. Free Mac’s free scan shows both on one map.

When I searched my MacBook Air, which was 97 percent full, I found just one file over 500 MB and 96 over 100 MB. The space wasn’t in big files. It was in caches, app data and build folders made of thousands of small ones.

Way 1: Storage settings

1. Open System Settings, General, Storage.
2. Click the info button next to Documents.
3. Open Large Files to see files sorted by size, and Downloads for old downloads.

It’s built in and safe, but it only lists single files, and it lumps a lot into System Data. I tried living with it for a week: I Gave macOS Storage Settings a Real Chance.

Way 2: Finder search by size

1. In Finder, press Command and F.
2. Choose This Mac.
3. Click the first filter, choose Other, then File Size.
4. Set it to is greater than 500 MB, then try 100 MB.

Good for videos and disk images. It misses hidden folders and anything made of many small files.

Way 3: Terminal

This lists files over 500 MB in your home folder, without changing anything:

find ~ -type f -size +500M

And this shows the biggest folders at the top level of your home folder:

du -sh ~/* | sort -rh | head

Avoid running these with sudo across the whole disk unless you know what you’re looking at.

Way 4: A disk map that shows folders too

Free Mac scans the whole Mac for free and draws it as one map, where each block’s size is its size on disk. Folders full of small files, like caches and developer folders, show up as big blocks instead of disappearing. Click into any block to see what’s inside. The full guide: how to find large files on a Mac.

Why people use Free Mac for this

• Scanning is free. Scan the whole Mac or one folder, see the map and every list, with no account and no trial timer.
• It shows what Finder hides: caches, app leftovers, build folders and old disk images, drawn as one map where the biggest block is the biggest problem.
• It says what’s safe. Each app’s real footprint is shown with its leftovers, and developer folders are marked when they rebuild themselves.
• Nothing is deleted outright. Cleaning moves files to the Trash, so you can put anything back.
• A subscription key unlocks cleaning, and it only asks at the moment you clean. It runs on macOS 10.15 or later.

Run the free scan from free-mac.online and see your own numbers first.

The folders a size search misses

• Caches: 11 GB on my Mac, all small files. See what’s safe in Library/Caches.
• App data in Application Support: 8.5 GB.
• Developer folders: about 29 GB when I measured them, including node_modules and package caches. I wrote it up here: Developer Folders Took 29 GB of My MacBook Air.
• iPhone backups and Time Machine snapshots. See iPhone backups taking up space.

Before you delete anything

• Move to the Trash first, empty it later.
• Keep a backup before a big cleanup.
• Leave system folders alone unless a guide says a folder is safe.

People also ask

How do I see what’s taking up space on my Mac?

Storage settings for a summary, or a disk map for every folder.

How do I find files over 1 GB on a Mac?

Finder search with File Size greater than 1 GB, or find ~ -type f -size +1G in Terminal.

Why can’t I find what’s using my storage?

Because it’s usually folders of small files and hidden Library folders, which file searches don’t show.

Where all 222 GB went on my Mac: My MacBook Air Had 6 GB Free. I Measured Where It Went.

Quick answer: quit the app, use its own uninstaller if it has one, then move it to the Trash and remove its leftover folders from your Library (Application Support, Caches, Preferences, Containers and Launch Agents). To find every leftover in one go, the free scan in Free Mac shows each app’s real footprint, leftovers included.

When I checked my MacBook Air, I found 11 folders over 50 MB, about 2 GB in total, that didn’t match any app still in my Applications folder. Every one was left behind by an app I’d “deleted”.

Why dragging to the Trash isn’t a full uninstall

An app is a single bundle in Applications, but while it runs it writes files all over your Library: settings, caches, downloaded data, helpers that start at login. The Trash only removes the bundle. The rest stays until you remove it yourself.

Way 1: Move the app to the Trash

1. Quit the app, including any icon it has in the menu bar.
2. Open Finder, Applications, right click the app and choose Move to Trash.
3. Empty the Trash when you’re sure.

This is enough for small apps. For anything big, carry on to remove the leftovers.

Way 2: Use the app’s own uninstaller

Apps that install drivers, background helpers or plug ins (security tools, audio apps, design suites, some games) usually come with an uninstaller. Look in the app’s folder, in its menu or on the developer’s site. Use it first: it knows where its own files are.

Way 3: Remove the leftovers by hand

In Finder, choose Go, Go to Folder and open each of these, looking for folders named after the app or its developer:

• ~/Library/Application Support: the app’s data. Usually the biggest.
• ~/Library/Caches: cached files.
• ~/Library/Preferences: settings files ending in .plist.
• ~/Library/Containers and Group Containers: data for App Store and sandboxed apps.
• ~/Library/Saved Application State: window positions.
• ~/Library/LaunchAgents and /Library/LaunchAgents: helpers that start at login.
• ~/Library/Logs: the app’s logs.

Only remove folders for apps you’ve actually uninstalled. If a name isn’t clearly the app’s, leave it. More on the folders in Library Containers taking up space.

Way 4: Apps installed with Homebrew

If you installed an app with Homebrew, brew uninstall — zap and the app’s name removes the app and the files its cask lists. Details: Homebrew zap and leftovers.

Way 5: An uninstaller that finds everything

Doing Way 3 for every app is slow. Free Mac’s Apps view finds the caches, containers and launch agents an app scattered, shows the total next to the app, then removes the lot together. More on why this beats the Trash: a Mac app uninstaller that finds leftovers.

Why people use Free Mac for this

• Scanning is free. Scan the whole Mac or one folder, see the map and every list, with no account and no trial timer.
• It shows what Finder hides: caches, app leftovers, build folders and old disk images, drawn as one map where the biggest block is the biggest problem.
• It says what’s safe. Each app’s real footprint is shown with its leftovers, and developer folders are marked when they rebuild themselves.
• Nothing is deleted outright. Cleaning moves files to the Trash, so you can put anything back.
• A subscription key unlocks cleaning, and it only asks at the moment you clean. It runs on macOS 10.15 or later.

Run the free scan from free-mac.online and see your own numbers first.

App won’t delete?

• “The item can’t be moved because it’s open”: quit it, then check Activity Monitor for its helper and quit that too.
• Built in apps that came with macOS can’t be removed, and shouldn’t be.
• An app comes back at login: its launch agent is still there. Remove it from the LaunchAgents folders above, or from Login Items in System Settings.

People also ask

Does deleting an app delete its data?

No. Settings, caches and app data stay in your Library until you remove them.

Is it safe to delete Application Support folders?

For apps you’ve uninstalled, yes. For apps you still use, no: that’s where their data lives.

What’s the difference between deleting and uninstalling?

Deleting removes the app. Uninstalling removes the app and everything it created. See delete vs uninstall on a Mac.

My years of dragging apps to the Trash, and what changed: I Uninstalled Mac Apps by Dragging Them to the Trash for Years.

The short answer: a lot of “System Data” is swap, temporary files and other people’s accounts on the same Mac. A restart clears most swap and many temporary files. Other accounts have to be cleaned from inside those accounts. To see which folders are actually big on your Mac, run the free scan in Free Mac.

When I measured my MacBook Air, the folders under /private/var alone held 10 GB, and none of it shows up in Finder.

1. Swap: 2 GB on my Mac

When memory fills up, macOS writes some of it to disk as swap. Mine was using 2 GB of a 3 GB swap allowance. It shrinks again when memory frees up, and a restart clears it. Never delete swap files by hand. More in swap and sleep image files.

2. Temporary folders: 5.2 GB

Apps keep caches and temporary files in hidden folders under /private/var/folders. macOS cleans many of them on restart. Deleting them by hand while apps are running can break those apps, so restart first and see what’s left. See what’s in /private/var/folders.

3. Other user accounts

My Mac has four other accounts besides mine. Their files sit on the same drive and count against your free space, but you can’t open them from your own account, so they look like a mystery. If an account belongs to someone who no longer uses the Mac, sign in as them, clear what they don’t need, or remove the account in System Settings, Users and Groups after keeping a backup. More in other users and shared storage and old user accounts taking up space.

4. Purgeable space

macOS also shows some space as purgeable: things it can remove on its own when it needs room, like cached copies of iCloud files. It’s real space, just not free yet. See purgeable space, explained.

Why people end up using Free Mac

• Scanning is free. Scan the whole Mac or any folder, see the map and the lists, with no account and no trial timer.
• It shows what Finder hides. Caches, build folders, old disk images and app leftovers, drawn as one map where the biggest block is the biggest problem.
• It says what is safe. For developer folders it tells you which ones rebuild themselves, and only counts a folder as build output when its project file sits beside it.
• Nothing is deleted outright. When you clean, files go to the Trash, so you can put anything back.
• Cleaning is unlocked with a subscription key, and you only need it at the moment you clean. It runs on macOS 10.15 or later.

Start with the free scan at free-mac.online and see your own numbers before deciding anything.

What to do, in order

1. Restart. It’s free and clears swap and many temporary files.
2. Scan to see which folders are big on your Mac.
3. Check other accounts if your Mac is shared or second hand.
4. Leave system folders alone unless a guide says a folder is safe.

Earlier on this blog: Mac System Data Over 100 GB? What’s Hiding in It.

How big is the grey System Data bar on your Mac?