Dupe guide

What is 'Other' storage on Mac and how to clean it

The mysterious 'Other' bar in macOS storage is mostly four specific things. Here's what it is and how to shrink it.

4 min read

You open About This Mac > Storage and there’s a fat grey bar labelled “Other” taking up 60 GB. Apple won’t tell you what’s in it. The good news: “Other” is almost always four specific things, and three of them are easy to clear.

What “Other” actually contains

The “Other” category catches everything macOS doesn’t know how to classify into Apps, Documents, Photos, Mail, etc. In practice that means:

  1. Caches. App caches, browser caches, Spotlight indexes — anywhere from 1–20 GB.
  2. Mail attachments and downloads. The Mail.app cache in ~/Library/Containers/com.apple.mail/Data/Library/Mail Downloads/ often appears here, not under "Mail."
  3. iOS backups and device support files. Old iPhone backups, simulator files for developers.
  4. "Unknown" file types. Disk images, plug-ins, fonts, anything macOS can't categorize.

Clearing it, in order

1. Mail downloads

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

If that’s more than 1 GB, open Mail > Settings > Accounts > Advanced and set “Download Attachments” to “None” or “Recent.” Then delete the contents of that Mail Downloads folder — Mail re-downloads from the server if you ever need them.

2. iOS backups

Open Finder, plug in your iPhone, click it in the sidebar, then “Manage Backups.” Delete any backups from devices you no longer own.

You can also see them directly:

ls -lah ~/Library/Application\ Support/MobileSync/Backup/

3. Caches

du -sh ~/Library/Caches/* 2>/dev/null | sort -h | tail -10

That lists your biggest cache folders. Caches are regenerated automatically — you can delete the contents of folders for apps you still use without breaking them, though next launch will be slightly slower.

Don’t delete the cache folders themselves, just their contents. And skip com.apple.dt.Xcode if you’re a developer who still uses Xcode unless you want to re-download SDKs.

4. Disk images and large unknowns

find ~ -type f \( -name "*.dmg" -o -name "*.iso" \) 2>/dev/null

DMGs and ISOs you’ve downloaded over the years often live in Downloads and don’t get classified anywhere obvious.

Duplicates are hiding here too

Files that “Other” classifies as unknown are often the same files in different formats — exported videos, archived ZIPs of folders you still have unzipped, screenshots saved twice. Download Dupe to find byte-identical copies. It hashes everything with SHA-256, scans wherever you point it, and moves dupes to the Trash so you can change your mind.

$14.99 one-time, never permanent deletes, never touches system files.

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