Before deleting anything, you need to understand what's occupying the space. macOS offers a built-in diagnostic tool: Apple menu → About this Mac → Storage (or System Settings → General → Storage on recent versions). A coloured bar shows the breakdown by category: Applications, Documents, Photos, System, Other.
The «System data» category (formerly «Other») is often the most mysterious and the largest. It includes application caches, temporary files, system logs, fonts, plug-ins and various support files. This is generally where the biggest gains are made.
For a more detailed view, open a Finder window and use Cmd + Shift + G to navigate to specific folders, or use Terminal with the command du -sh ~/Library/Caches/* to measure cache size. Our complete guide cleaning your Mac details advanced diagnostic tools and methods.
These actions take less than five minutes and often free up several gigabytes.
It sounds obvious, but the recycle bin in macOS can contain tens of gigabytes of deleted files. Right-click on the Recycle Bin icon in the Dock → Empty Recycle Bin. For automatic cleaning, enable «Automatically delete items from the recycle bin after 30 days» in Finder → Settings → Advanced.
The Downloads folder is a trap for forgotten files: .dmg installers, .zip archives already extracted, PDFs read only once, images downloaded months ago. Open ~/Downloads, sort by size (Overview → Sort by → Size) and delete anything that's no longer useful. The .dmg installers in particular are of no use once the application has been installed.
If you regularly use Cmd + Shift + 3 or 4 to capture your screen, the desktop (or the destination folder you've set up) can accumulate hundreds of captures. Sort through them, archive the useful ones and delete the rest. To master the capture options, see our Mac screen capture guide.
iCloud storage optimization is the most elegant solution for Macs with a small-capacity SSD. The principle: macOS keeps recently used files locally and automatically offloads older files to iCloud, keeping only a light version (thumbnail for photos, empty file for documents). When you open a downloaded file, macOS automatically re-downloads it.
| iCloud package | Storage | Price/month | Ideal for |
|---|---|---|---|
| Free | 5 GB | 0 € | Basic backup only |
| iCloud+ 50 GB | 50 GB | 0,99 € | Modest photo library, a few documents |
| iCloud+ 200 GB | 200 GB | 2,99 € | Full personal use, family sharing |
| iCloud+ 2 TB | 2 To | 9,99 € | Large photo libraries for professional use |
| iCloud+ 6 TB | 6 To | 29,99 € | Video production, large archives |
| iCloud+ 12 TB | 12 To | 59,99 € | Extreme professional needs |
Dragging an application to the recycle bin does not delete all its associated files. MacOS applications leave behind preference files, caches, support files and logs scattered around the ~/Library folder. Over the years, this residue can amount to several gigabytes.
For applications installed from the App Store: Launchpad → hold click on the icon → click on the «X» that appears. For others, drag the application from /Applications to the recycle bin. Some apps (such as Adobe Creative Cloud) have their own uninstaller - use that rather than the manual method.
After deleting an application, check the following locations and delete any folders named after the application:
~/Library/Application Support/~/Library/Caches/~/Library/Preferences/~/Library/Saved Application State/To access the Library folder (hidden by default), open the Finder and press Cmd + Shift + G, then type ~/Library.
Caches are temporary files created by macOS and applications to speed up their operation. They are supposed to manage themselves automatically, but in practice they swell over time - especially the caches of web browsers and authoring software.
| Cache | Location | Typical size | Impact of deletion |
|---|---|---|---|
| Browser caches | ~/Library/Caches/com.apple.Safari/ or Google/Chrome/ | 500 MB to 5 GB | Slightly slower loading of sites temporarily |
| Application caches | ~/Library/Caches/ | 1 to 10 GB | Slower first launch, rebuilds automatically |
| System covers | /Library/Caches/ | 500 MB to 2 GB | Rebuilds automatically |
| System logs | ~/Library/Logs/ and /var/log/ | 200 MB to 2 GB | No functional impact |
| Local Time Machine copies | Managed by macOS | Several Go options | macOS automatically deletes them when space runs out |
The biggest files on a Mac are often the ones you've forgotten existed: an old video editing project, a local iPhone backup, a Windows virtual machine, .ipa files from old iOS backups.
In System Settings → General → Storage, click on each category to explore its contents. The «Documents» tab is particularly useful - it displays files sorted by size, with the date they were last accessed. Large files that you haven't opened for months are the first candidates for deletion or archiving.
Open the Finder, launch a search (Cmd + F), change the criterion from «Name» to «File size» → «is greater than» → 500 MB. You'll probably discover some large files forgotten in unexpected folders. For other advanced search techniques, see our Finder Mac tips.
When cleaning isn't enough - or if your Mac has a small-capacity SSD that can't be upgraded (all Apple Silicon Macs) - an external drive is the most pragmatic solution. A 1TB USB-C external SSD costs less than €100 and offers sufficient speed for most uses.
To choose the right external SSD, consult our test of the best SSDs for Mac. And to compress large files before archiving them, our guide compress files on the Mac provides details of the best methods and formats. Apple also offers its own recommendations for freeing up storage space.
«System data» (formerly «Other») includes application caches, temporary files, system logs, fonts, plug-ins, application support files and local Time Machine copies. This category can take up 10 to 50 GB or more. Most of these files can be safely cleaned - the caches rebuild automatically.
Yes, in most cases. Caches in ~/Library/Caches/ can be safely deleted - applications will automatically recreate them as required. The only drawback is that some applications will take slightly longer to load the first time. Avoid deleting system caches in /System/Library/ as this can cause instabilities.
Start with the biggest gains: empty the recycle bin, clean up downloads, delete unused apps. Then use System Settings → General → Storage to identify the largest categories. Finder searches by size (over 500 MB) often reveal overlooked files.
No. Your files remain in iCloud and can be accessed at any time. macOS simply replaces local files with «stubs» (reference files) that weigh just a few bytes. When you open an unloaded file, macOS automatically re-downloads it. You need an Internet connection to access the downloaded files.
Local iPhone and iPad backups can take up dozens of gigabytes. Go to Finder (on macOS Catalina and later), connect your iPhone, click on «Manage backups» and delete any old, unnecessary backups. If you use iCloud backup for your iPhone, local backups are superfluous.
This is rarely necessary. The tools built into macOS and the manual methods described in this guide cover the vast majority of needs. If you opt for a third-party tool, choose reputable applications such as OnyX (free) or CleanMyMac. Avoid «cleaning» software that promises miraculous performance - it's often scareware or adware.
Enable iCloud storage optimisation, set the recycle bin to empty automatically after 30 days, get into the habit of cleaning out the Downloads folder every week, and archive completed projects on an external drive. Just 10 minutes' maintenance a month is all it takes to keep your Mac clean.
The general rule is to maintain at least 10 to 20 % of free disk space. macOS uses free space for swap (virtual memory), temporary files, updates and caches. Below 10 %, performance degrades significantly and certain operations (macOS updates, video exports) may fail.
The internal SSD in Apple Silicon Macs is soldered and non-replaceable. The only option is to use an external drive - a USB-C or Thunderbolt SSD offers excellent performance. For older Macs with replaceable SSDs, see our SSD upgrade guide.
Yes, with over 15 years' experience since 2010, our team carries out a complete clean-up: deleting unnecessary files, optimising the system, checking the state of the disk and SSD upgrades if the model allows. 180-day guarantee. Take appointment or request a free diagnosis.
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