How to Free Up Space on Mac: 15 Safe Ways That Actually Work

The “Your disk is almost full” warning always shows up at the worst moment: in the middle of an update, an export, or a video call recording. And Storage settings rarely makes it obvious what to delete.

This guide is the order I'd work in on any Mac. It starts with the steps that take two minutes and can't go wrong, then moves to the bigger jobs. Every step uses what's already on your Mac. I build a disk space app, and I'll mention it near the end, but you don't need it for anything here.

First, see what's using your space

Spend one minute here before you delete anything. It tells you which of the steps below are worth your time. On macOS Ventura and later, open:

You'll see a coloured bar and a list of categories: Applications, Documents, Photos, Messages, iCloud Drive, macOS, System Data and so on. Wait a minute or two for the numbers to settle. Then look at the two or three biggest rows. That's where to spend your effort.

• Documents is big? Go to step 6. Large files and old downloads are hiding there.
• Applications is big? Step 5. Apps you've forgotten about add up fast.
• Photos or Messages is big? Steps 9 and 10.
• System Data is big? That's its own puzzle. See What Is System Data on Mac.

Most rows have an ⓘ button. Click it to see what's inside and delete things right from that window. The one for Documents is the most useful, and step 6 shows it.

How much free space does a Mac need?

Apple doesn't give one number, but macOS clearly needs room to work. It uses free space for memory swap, Time Machine snapshots, caches and updates. These ranges are a fair guide:

Before you delete anything

Three rules keep this safe:

1. Back up first. If you use Time Machine or another backup, let it finish a run before you start.
2. Move to the Trash, then wait. Empty the Trash only after a day or two of everything working normally. Avoid rm commands copied from forums, which skip the Trash entirely.
3. If you don't know what it is, leave it. No amount of free space is worth a Mac that won't start, or a lost file you needed.

Quick wins: 4 steps, about 10 minutes

Do these first. They're safe, fast and often enough on their own.

1Empty every Trash, not just the one in the Dock

Files in the Trash still use space. Control-click the Trash in the Dock and choose Empty Trash. Then check the two other places that keep deleted things:

• Photos: open the Recently Deleted album. Photos keeps deleted pictures and videos there for about 30 days. Click Delete All if you're sure.
• Mail: Control-click the Trash and Junk mailboxes and choose Erase Deleted Items and Erase Junk Mail.

2Clear out your Downloads folder

Downloads is where installers, zip files and one-off videos go to be forgotten. On most Macs it's the easiest big win.

1. Open Downloads in Finder and switch to list view (⌘ 2).
2. Click the Size column header so the biggest files come first.
3. Remove installers you've already used (.dmg, .pkg), zip files you've already opened, and anything you can download again.

3Delete old macOS installers

If you've ever downloaded a macOS upgrade without installing it right away, you may have an app called Install macOS Sonoma (or another version name) sitting in Applications. Each one is around 12 to 15 GB. Once you're running that version or later, it's safe to move to the Trash.

Open Applications in Finder, sort by name and look for anything starting with Install macOS. Check Downloads too, in case one landed there.

4Turn on Storage recommendations

At the top of Storage settings, macOS offers a few switches that free space now and keep it free later:

• Store in iCloud keeps older files, photos and messages in iCloud and downloads them when you open them. Only useful if you have enough iCloud storage.
• Optimize Storage removes movies and TV shows you've already watched in the Apple TV app.
• Empty Trash Automatically removes anything that's been in the Trash for 30 days, so step 1 takes care of itself.

Worth 15 minutes: steps 5 to 8

If the quick wins weren't enough, these four usually are. Each takes a bit of looking, but this is where most of the space is.

5Uninstall apps you don't use, and their leftovers

In Storage settings, click ⓘ next to Applications. You get every app with its size and when you last opened it. Sort by size, and look for apps you haven't used in months: games, video editors, trial apps, that one tool you needed for a single project.

Select an app and click Delete, or drag it from the Applications folder to the Trash. Apps installed from the App Store can also be removed from Launchpad by holding an icon until it jiggles.

6Find your largest files

A handful of big files usually takes more space than thousands of small ones. There are two built-in ways to find them.

From Storage settings. Click ⓘ next to Documents. The Large Files tab lists your biggest files with the date you last opened them. The Downloads and Unsupported Apps tabs are worth a look too. Select anything you don't need and click Delete.

From Finder. This finds big files anywhere, not only in Documents:

1. Open a Finder window and press ⌘ F. Click This Mac.
2. Click the Kind menu and choose Other…. Tick File Size in the list and click OK.
3. Set it to is greater than 1 GB. Switch to list view and sort by Size.

Things that often turn up, and what to do with them:

• Screen recordings and exported videos. Keep the final cut, delete the raw takes, or move them to an external drive (step 15).
• Virtual machine disks (.vhdx, .pvm, .utm). If you no longer use the VM, delete it from inside Parallels, UTM or VMware so it cleans up properly.
• Zip and disk image files you've already opened or installed.

7Clear app caches

Apps keep copies of things they downloaded or worked out before, so they open faster. Browsers, Spotify, Slack, Adobe apps and Homebrew can each hold several gigabytes, and they rarely clean up after themselves.

1. In Finder, choose Go → Go to Folder (⇧ ⌘ G) and type ~/Library/Caches.
2. In list view, choose View → Show View Options and tick Calculate all sizes. Sort by Size.
3. Quit the app a big folder belongs to, then move that folder to the Trash.
4. Restart. Apps build fresh, smaller caches next time you open them.

Trash the folders inside Caches, never the Caches folder itself. For browsers, clearing the cache in the browser's own settings is cleaner and keeps you signed in. The System Data guide has more detail and a picture of this step.

8Delete old iPhone and iPad backups

Each backup can be as large as the device's used storage, and Macs quietly keep backups of phones you sold years ago.

1. Connect any iPhone or iPad, then click it in the Finder sidebar.
2. On the General tab, click Manage Backups.
3. Select backups you don't need and click Delete Backup.

Keep the newest backup of the device you use today, unless it backs up to iCloud. To see the total size without a device, open ~/Library/Application Support/MobileSync/Backup with Go to Folder.

Bigger jobs: steps 9 to 15

You probably don't need all of these. Use what Storage settings showed you at the start to pick the ones that apply.

9Slim down your Photos library

A Photos library can quietly reach 100 GB or more. Three ways to shrink it:

• Use iCloud Photos with Optimize Mac Storage. In Photos, choose Photos → Settings → iCloud and select Optimize Mac Storage. Full-size originals stay in iCloud, and your Mac keeps smaller versions that download in full when you open them. This needs enough iCloud storage for your whole library.
• Merge duplicates. Recent versions of Photos have a Duplicates album in the sidebar. Open it and merge the copies.
• Delete long videos you don't need. In the sidebar, open Media Types → Videos. A few minutes of 4K video can be several gigabytes. Then empty Recently Deleted (step 1).

10Clear out Messages attachments

Every photo, video and sticker anyone has sent you is saved on your Mac, sometimes for years. In Storage settings, click ⓘ next to Messages to see the biggest attachments and delete them.

To stop it piling up again, open Messages → Settings → General and set Keep messages to 1 Year or 30 Days. Be sure first: this deletes older conversations along with their attachments.

11Clear Mail's downloaded attachments

When you open an attachment in Apple Mail, a copy is saved on your Mac. Those copies live in a folder most people never see:

$ du -sh ~/Library/Containers/com.apple.mail/Data/Library/Mail\ Downloads

If it's large, open that folder with Go to Folder and move what you don't need to the Trash. The originals stay in your email. Then, in Mail → Settings → General, set Remove unedited downloads to After Message is Deleted.

12Let iCloud Drive keep files online

If you use iCloud Drive, your Mac can keep a copy of everything, or only what you use. In System Settings → your name → iCloud, turn on Optimize Mac Storage (on some versions it's under iCloud Drive). macOS then removes local copies of older files when space runs low, and downloads them again when you open them.

To free space right away, Control-click a big file or folder in iCloud Drive and choose Remove Download. It stays in iCloud and on your other devices.

13Remove duplicate files

Duplicates come from downloading the same file twice, copying folders “just in case” and importing photos more than once. macOS has no built-in duplicate finder outside Photos.

By hand, the most reliable approach is the Finder search from step 6: sort large files by size and look for pairs with the same size and similar names. Open both before deleting one. Files with the same name aren't always the same file, and files with different names sometimes are.

14Clear developer data (if you write code)

If you've installed Xcode or Docker, this can free more than every other step combined. Xcode's build folders, old simulators and device support files, Docker's disk image and forgotten node_modules folders regularly add up to 50 GB or more. All of it is rebuilt or downloaded again when you need it.

$ xcrun simctl delete unavailable

The System Data guide goes through Xcode DerivedData, device support, Docker and package caches one by one.

15Move big media to an external drive

Some things are big and worth keeping: video projects, raw photo shoots, music sample libraries, old project archives. They don't need to live on your Mac's internal drive.

• A USB-C SSD is fast enough to edit from directly, and a 1 TB one costs less than most storage upgrades.
• Copy first, check the copy opens, then delete the original. Never move your only copy of something in one step.
• Keep a backup of the external drive too. A drive that holds the only copy of your files is a risk, not a backup.
• Music apps can store their sound libraries elsewhere. Logic Pro, for example, can relocate its library from Logic Pro → Sound Library.

Still full? Check System Data

If you've worked through the steps and the bar barely moved, look at the System Data row in Storage settings. If it's 50 GB or more, that's probably where your space went: local Time Machine snapshots, caches, old backups and app leftovers that macOS doesn't put into a clearer category.

I wrote a separate guide for that: What Is System Data on Mac, and How Do You Reduce It? It covers snapshots, which are often the single biggest win, along with the Terminal commands to remove them safely.

Also restart your Mac. It clears swap and temporary files, and makes Storage settings count everything again.

What not to do

Some popular advice frees space and creates new problems. Skip these:

• Don't delete anything in /System, /private/var or /usr. Most of it is protected anyway, and the rest is there for a reason.
• Don't empty your whole ~/Library folder. It holds your settings, passwords, mail and app data, not just caches.
• Don't paste sudo rm -rf commands from forums unless you understand every part. They delete instantly, with no Trash.
• Don't turn off Time Machine to save space. Keep the backups and let macOS manage the local snapshots.
• Don't reinstall macOS as a first move. It takes hours and rarely frees more than the steps above.
• Be wary of cleaner apps that won't show you what they delete. A good tool lists every file, lets you choose, and moves things to the Trash so you can change your mind.

The faster way: see everything in one window

Everything above works. It also means opening a dozen folders and settings panes, and remembering which file you saw where. That's why I built DiskMate. It does most of these steps in one window:

• Steps 2, 6 and 15 in one view. The Space page ranks every folder and file by size, as a list or a treemap you can click into. The Old files page lists big files you haven't touched in over a year.
• Steps 7 and 14 as a checklist. Cleanup finds caches, logs, Xcode build files and node_modules folders, adds them up and lets you tick what goes.
• Step 5 including leftovers. The Apps page shows each app's real size including its files in ~/Library, and removes them together.
• Step 13 done properly. Duplicates are confirmed byte for byte with SHA-256, not guessed from names.
• Nothing disappears by surprise. Everything goes to the Trash first, and nothing leaves your Mac.

Quick checklist

Bookmark this for the next time the “disk almost full” warning shows up:

Frequently asked questions