If your Mac is warning you that the startup disk is almost full, you're not alone. macOS quietly accumulates gigabytes of caches, old backups, duplicate downloads, mail attachments, and system logs that most users never see. The good news: you can usually recover 20 GB to over 100 GB in under an hour, without buying any software.
This complete guide walks you through eight proven methods to free up space on Mac, from the built-in storage manager to carefully chosen Terminal commands. Everything here works on macOS Sonoma, Sequoia, and newer versions, including both Intel and Apple Silicon Macs.
1. Check Your Mac's Storage First
Before deleting anything, understand what's actually eating your disk. macOS includes a built-in storage inspector that categorizes everything on your drive into Applications, Documents, Mail, Photos, System Data, and more.
Open the Apple menu () → System Settings → General → Storage. Wait a few seconds while macOS scans your disk. You'll see a colored bar at the top showing how your storage is distributed.
Pay special attention to two categories:
- System Data (previously called "Other") — often the biggest surprise. It includes caches, logs, plugin data, and leftover installer files.
- Documents — click "Documents" to see a breakdown of large files, downloads, and unsupported file types taking up space.
For a Terminal-based breakdown of your home folder, run:
du -sh ~/* 2>/dev/null | sort -hThis lists every top-level folder in your home directory sorted by size — a quick way to spot a bloated ~/Movies, ~/Downloads, or ~/Library.
Rerun the storage view every time you finish a cleanup step. Watching "System Data" shrink in real time is both satisfying and a great way to confirm your changes worked.
2. Empty Trash and Clean Up Downloads
The easiest win first. The Trash can hold tens of gigabytes you've already "deleted" but never purged. Right-click the Trash icon in the Dock → Empty Trash, or press ⌘ + Shift + Delete in Finder.
Modern macOS supports per-folder Trash on external drives and iCloud. Open Finder, press ⌘ + Shift + . to reveal hidden folders, and empty every .Trashes folder on your mounted volumes.
Next, tackle the Downloads folder. For most people this is the single most bloated folder on the entire Mac — full of DMG installers, PDFs opened once, and old ZIPs. Open Finder → Downloads, switch to list view, and sort by Size (click the column header; add it via View → Show View Options if hidden).
To find and remove old DMG and PKG installer files, run:
find ~/Downloads -type f \( -name "*.dmg" -o -name "*.pkg" \) -mtime +30 -printThis lists installer files older than 30 days. Review the list carefully, then delete them with Finder or append -delete only after you've verified the output.
3. Clear System and User Caches
Caches are temporary files that apps keep around to speed up repeated operations. Over months and years they can balloon to many gigabytes. macOS does not automatically clean them, so manual cleanup is safe and often very effective.
First, see how big your user cache is:
du -sh ~/Library/CachesIf the result is more than 2–3 GB, it's worth cleaning. Quit all open apps first, then run:
rm -rf ~/Library/Caches/*This wipes the contents of your user caches folder but keeps the folder itself intact, which is exactly what macOS expects. Apps will rebuild only the caches they actually need.
Never delete the ~/Library/Caches folder itself — only its contents. Also avoid wiping system-level caches at /Library/Caches or /System/Library/Caches unless you have a specific reason; macOS manages those automatically.
For a deeper walkthrough of safe vs. unsafe caches, see our dedicated clear cache on Mac guide.
4. Remove Old iOS and iPadOS Backups
If you've ever backed up an iPhone or iPad to your Mac via Finder (or iTunes on older macOS), those backups live on your startup disk and can be enormous — often 30–80 GB each. Multiple old backups of devices you no longer own are pure waste.
List all local device backups with:
ls -lah ~/Library/Application\ Support/MobileSync/Backup/Each subfolder is one device backup. To delete backups from the GUI, open Finder, connect your device (or not — it's not required), go to System Settings → General → Storage → iOS Files on recent macOS versions, and remove backups you no longer need. Alternatively, in Finder → your device → Manage Backups.
If a backup folder is from an old device you've long since replaced, you can safely remove it with:
rm -rf ~/Library/Application\ Support/MobileSync/Backup/DEVICE_ID_HEREReplace DEVICE_ID_HERE with the actual folder name shown by the ls command. Double-check before pressing Enter — this operation is immediate and cannot be undone.
5. Manage Large Files with Finder
Finder has a hidden feature most users miss: a built-in "Large Files" filter accessible through the Storage settings. Go to System Settings → General → Storage, click the ⓘ next to Documents, then switch to the Large Files tab. You'll see every file over 50 MB sorted by size.
To search even more aggressively from Terminal, list every file over 500 MB on your Mac:
sudo find / -type f -size +500M -not -path "/System/*" -not -path "/private/*" 2>/dev/nullCommon culprits include forgotten video exports, GarageBand/Logic project archives, virtual machine disk images (.vmdk, .vmwarevm, .utm), and old Final Cut Pro libraries. Delete only files you recognize as truly unneeded, and consider moving large video or archive files to an external SSD before deleting the originals.
In Finder, hit ⌘ + F, choose This Mac, click the "+" button, pick File Size → is greater than → 1 GB, and you'll get a live view of every file above a gigabyte without using Terminal.
6. Enable macOS Optimize Storage
Apple ships a quietly powerful set of "Recommendations" that most users never enable. In System Settings → General → Storage, scroll to the Recommendations section. You'll see three toggles:
- Store in iCloud — automatically offloads old Documents, Desktop files, and Photos originals to iCloud when disk space is low. Local copies are replaced with lightweight placeholders.
- Optimize Storage — removes Apple TV movies and shows you've already watched, and keeps only recent email attachments on-disk.
- Empty Trash Automatically — permanently deletes items that have been in the Trash for more than 30 days.
Enabling all three is a reasonable default for most users. If you have a tiny iCloud plan or very limited internet, enable only "Empty Trash Automatically" and skip the rest.
7. Use iCloud to Offload Files
Even if you don't enable the automatic "Store in iCloud" option, you can manually offload specific folders. Right-click any file in Finder with iCloud Drive enabled and choose Remove Download. The file remains visible in Finder but its local data is deleted; macOS re-downloads it on demand.
To check how many files are currently cached locally in iCloud Drive:
du -sh ~/Library/Mobile\ Documents/com~apple~CloudDocsIf the result is 20+ GB, selectively right-clicking large folders and choosing "Remove Download" can reclaim significant space without actually losing anything — the files remain in iCloud and reappear when you open them.
8. Clean Up Mail Attachments
If you use Apple Mail with IMAP accounts, every attachment you've ever received may be cached locally. For heavy email users, the Mail downloads folder can hold 10–50 GB of orphaned attachments.
Check its size:
du -sh ~/Library/Containers/com.apple.mail/Data/Library/Mail\ Downloads 2>/dev/nullTo delete only the cached attachment downloads (safe — Mail will re-download them on demand):
rm -rf ~/Library/Containers/com.apple.mail/Data/Library/Mail\ Downloads/*You can also tell Mail to stop auto-downloading attachments: Mail → Settings → Accounts → [your account] → Account Information → Download Attachments: None.
Always have a current Time Machine backup before running rm -rf on any folder. The command is immediate, unrecoverable, and does not use the Trash. If you're not fully comfortable with Terminal, perform all cleanup via Finder and System Settings instead — the results are nearly identical.
Wrapping Up
After working through all eight sections, restart your Mac. Many caches are only truly released after a reboot, and macOS runs several background maintenance tasks within the first minutes after a cold boot. Then revisit System Settings → General → Storage and compare the new numbers with where you started.
If you still feel cramped for space, the next logical step is a dedicated cache deep-dive — see our how to clear cache on Mac guide — followed by removing apps you no longer use with our uninstall apps on Mac walkthrough.