Mac 'Other' Storage Explained: What It Is and How to Clear It

If you have ever opened About This Mac → Storage and stared at a massive gray or purple bar labeled Other, you are not alone. What is Other storage on Mac is one of the most searched Mac questions — and for good reason: it can balloon to 30 GB or more with no obvious explanation. This guide clarifies what counts as Other (and why Apple renamed it to System Data in macOS Monterey and later), which parts are safe to remove, and the exact steps to reclaim that space.

What Is 'Other' Storage on Mac? (And Why It's Now Called System Data)

Apple has used the label Other since the early days of the Storage overview in macOS. Starting with macOS Monterey (12), Apple split the old Other bar into two separate categories:

• System Data — caches, logs, temp files, Time Machine local snapshots, Siri voices, iCloud Drive cache, and miscellaneous app support files.
• macOS — the operating system itself (previously bundled inside Other on older macOS releases).

If you are on macOS Ventura, Sonoma, Sequoia, or newer, you will not see an "Other" bar at all — you will see System Data. If you are still on Big Sur or Catalina, the label is still Other. The underlying content is essentially the same; only the name changed.

What Historically Counted as 'Other'

Across macOS versions, the files lumped into Other / System Data have included:

• User and system caches (~/Library/Caches and /Library/Caches)
• Application logs (~/Library/Logs and /var/log)
• Temporary files (/private/var/folders/…)
• Time Machine local snapshots (stored on-disk when a backup drive is not connected)
• iOS device backups (~/Library/Application Support/MobileSync/Backup)
• App support data that does not fit the Documents or Apps categories
• Font files, preference files (~/Library/Preferences), browser caches
• Siri voices, dictation models, language packs
• Virtual machine disk images (.vmdk, .sparseimage)
• Purgeable space — files macOS has already identified as safe to remove but has not yet deleted

Because the category is a catch-all, it is almost always larger than it needs to be.

Is a Large 'Other' / System Data Normal?

Yes — to a point. macOS deliberately keeps caches and local snapshots to make your Mac feel fast and to give Time Machine breathing room. A System Data figure between 10–20 GB is typical on a well-used Mac. Anything above 40 GB usually means stale caches, old iOS backups, or Time Machine snapshots that have not been cleared in a long time.

What's Safe to Delete vs. What to Leave Alone

Important: Disk cleanup is permanent. Always back up to Time Machine or another destination before deleting anything you are unsure about.

How to Clear Other Storage on Mac — Step by Step

Method 1: Use macOS Built-In Storage Management

1. Click the Apple menu → System Settings (or System Preferences on macOS Monterey and earlier).
2. Go to General → Storage (or About This Mac → Storage → Manage on older macOS).
3. Review Recommendations: enable Optimize Storage and Empty Trash Automatically if you have not already.
4. Click System Data (or Other) in the sidebar to see a breakdown of what is consuming space. Note: macOS gives limited detail here.

Method 2: Clear User Caches Manually with Terminal

User caches are the largest safe target. Open Terminal (Applications → Utilities → Terminal) and run:

# List the largest cache folders first so you know what you're deleting
du -sh ~/Library/Caches/* 2>/dev/null | sort -rh | head -20

# Delete the entire user cache directory (apps will rebuild on next launch)
rm -rf ~/Library/Caches/*

After this, relaunch any open apps and reboot your Mac.

Method 3: Delete Old iOS Backups

iOS backups frequently claim 5–20 GB each and are easy to overlook.

1. Open Finder.
2. In the menu bar, choose Go → Go to Folder and enter: ~/Library/Application Support/MobileSync/Backup
3. Each subfolder is a device backup. The folder names are device UUIDs — connect the device in Finder to match names.
4. Delete backups for devices you no longer own, keeping the most recent backup for any device you still use.

Alternatively: open Finder → select your iPhone → Manage Backups for a friendlier interface.

Method 4: Delete Time Machine Local Snapshots

If your backup drive has been disconnected for a while, local snapshots can stack up. List and delete them with Terminal:

# List all local snapshots
tmutil listlocalsnapshots /

# Delete all local snapshots (macOS will recreate them on the next backup)
for snapshot in $(tmutil listlocalsnapshots / | grep 'com.apple.TimeMachine' | awk -F'.' '{print $4"."$5"."$6}'); do
  tmutil deletelocalsnapshots "$snapshot"
done

Method 5: Clear System Logs

# Remove user-level logs (safe)
rm -rf ~/Library/Logs/*

# Remove system logs (requires admin password)
sudo rm -rf /var/log/*
sudo rm -rf /Library/Logs/*

Method 6: Use Crumb to See What's Actually Hidden Inside System Data

The manual Terminal approach works, but it takes time and requires you to know which folders are safe. Crumb gives you a disk treemap that breaks down exactly what is inside your System Data / Other category — caches, logs, app support leftovers, and more — before you delete anything. Its built-in "Is this safe to delete?" feature explains any unfamiliar folder in plain English, so you are not guessing. One-click Clean handles system caches, user caches, logs, and purgeable space in a single pass. You can download Crumb and run the free cleanup to see how much it finds.

Why Does Other / System Data Keep Coming Back?

Caches and logs are a feature, not a bug — your Mac regenerates them continuously as you use apps, browse the web, and run system processes. Expect System Data to grow again within days of a cleanup. The goal is not to keep it at zero but to periodically clear the stale accumulation (old iOS backups, outdated cache versions, logs from months ago) so the total stays reasonable.

A useful habit: clear caches and logs every few months, audit iOS backups whenever you upgrade a device, and let macOS handle purgeable space on its own.

Quick Reference: Common Other / System Data Locations

• ~/Library/Caches — User app caches (safe to clear)
• /Library/Caches — System-level caches (safe to clear with caution)
• ~/Library/Logs — User logs (safe to clear)
• /var/log — System logs (safe to clear with sudo)
• ~/Library/Application Support/MobileSync/Backup — iOS backups
• ~/Library/Application Support — App support data (review before deleting)
• /private/var/folders — Temporary files (macOS manages these; avoid manual deletion)

Conclusion

The Other category on older macOS and the System Data bar on macOS Monterey and later both point to the same messy pile: caches, logs, snapshots, iOS backups, and app leftovers that pile up over time. Most of it is safe to clear with the right approach — user caches, old logs, stale iOS backups, and Time Machine local snapshots are the best targets. Just avoid touching system frameworks and preference files. Whether you prefer Terminal commands for full control or a tool like Crumb to visualize what is eating your disk before you act, the main thing is understanding what you are deleting and backing up first.