DaisyDisk Hidden Space: How to Find and Delete It on Mac

It is one of the most common and infuriating scenarios for Mac users: you open DaisyDisk hoping to clear space, only to be confronted by a giant, unclickable gray wedge taking up 40GB, 60GB, or even 100GB of your drive.

The label simply reads "Hidden Space". You cannot open it. You cannot drag it into the deletion drawer. And when you click on it, the app offers little more than a suggestion to read documentation or run as administrator.

Why does this ghost storage exist, why does DaisyDisk leave you stranded, and how do you actually get those gigabytes back? In this guide, we demystify Hidden Space and provide step-by-step solutions tested hands-on by our team.

What is "Hidden Space" in DaisyDisk?

To understand Hidden Space, you first need to understand how DaisyDisk measures your hard drive.

When DaisyDisk scans your internal drive, it asks the Apple File System (APFS) for two separate pieces of data:

1. Total Used Space: The exact number of bytes the operating system reports as physically occupied on the disk.
2. Scannable Files: The total size of all individual files and folders DaisyDisk's scanner was able to index under your user account permissions.

In an ideal world, those two numbers would match. But on modern Macs, they rarely do. Hidden Space is the mathematical difference between what macOS reports as used space and what DaisyDisk can actually see.

Because DaisyDisk cannot account for this gap by pointing to a specific folder on your desktop, it groups the missing gigabytes into a gray wedge and marks it "hidden."

The 3 Culprits Behind Hidden Space

Contrary to popular myths on forum boards, Hidden Space is almost never a corrupt file system or a hidden virus. In real daily use on modern Macs, three specific system elements account for 99% of this phantom usage:

1. Local APFS Time Machine Snapshots (The Top Culprit)

If you use Apple's built-in Time Machine backup feature on a MacBook, macOS automatically creates "local snapshots" on your internal solid-state drive whenever your external backup disk is not connected.

Here is the trap: an APFS snapshot freezes the state of your drive at a specific moment in time. If you delete a 40GB folder of video files from your desktop, macOS does not actually release that space. Instead, the snapshot preserves the deleted files so you can roll back your system if needed.

DaisyDisk cannot see the 40GB video folder anymore because you deleted it from Finder, but your SSD cannot free the storage blocks because the local snapshot still anchors them. The result? DaisyDisk classifies that 40GB as Hidden Space.

2. macOS Purgeable Space and Virtual Memory Buffers

Apple introduced the concept of "Purgeable Space" to optimize system responsiveness. macOS caches movie streaming buffers, iCloud photos, local font caches, and sleep image snapshots on your internal drive.

Apple's philosophy is that empty storage is wasted storage. The operating system holds onto these cached files until your disk becomes critically full, promising to clear them automatically when you need room. However, DaisyDisk cannot inspect or force-clear these purgeable system buffers, leaving them stranded in the gray Hidden Space category.

You can estimate your current reclaimable cache volume using our free Mac System Data Estimator.

3. Elevated Root Directories and Other User Accounts

When you run DaisyDisk normally, it runs with your standard macOS user account permissions. It cannot look inside:

• Directories created by other user profiles on the same computer.
• System logs and diagnostic folders in /private/var/log.
• Sandbox containers used by system daemons.

Since DaisyDisk is denied read access to these folders, it cannot calculate their individual contents and dumps their total volume into Hidden Space.

Why DaisyDisk Cannot Delete Hidden Space

Many users who purchase DaisyDisk feel frustrated when they realize the app cannot delete the largest chunk of clutter on their drive. In our hands-on DaisyDisk review, we highlighted this as its primary architectural limitation.

DaisyDisk is engineered as a storage visualizer, not an active system cleaner. Its core strength is generating fluid sunburst diagrams from file system metadata. It does not possess:

• An APFS snapshot pruning engine to safely thin Time Machine backups.
• Cache flushing routines to purge locked system buffers.
• Safety ratings to explain what files are safe to delete.

While DaisyDisk allows you to click "Scan as Administrator," this only solves the third culprit (permissions). It reveals some hidden root folders, but it does absolutely nothing to purge local APFS snapshots or purgeable space. You are left staring at the problem with no button to fix it.

How to Delete Hidden Space Manually (Terminal Method)

If you are comfortable using the macOS Terminal, you can manually delete local Time Machine snapshots without buying any additional software.

Before beginning, understand The Two-Vault System: modern macOS seals the core operating system on a cryptographically locked volume (the Signed System Volume). Purging local snapshots operates strictly within your personal data volume. It is safe and will not harm macOS or stop your computer from starting up.

Step 1: Check for Local Snapshots

Open Terminal (located in /Applications/Utilities/Terminal.app) and run the following command:

tmutil listlocalsnapshots /

If local snapshots exist on your drive, you will see a list of date-stamped entries formatted like this:

com.apple.TimeMachine.2026-09-21-143022.local
com.apple.TimeMachine.2026-09-22-091544.local
com.apple.TimeMachine.2026-09-23-180210.local

Step 2: Delete Snapshots One by One

To delete a snapshot and reclaim the storage it holds, run the deletion command with administrator privileges followed by the date stamp:

sudo tmutil deletelocalsnapshots 2026-09-21-143022

Type your Mac login password when prompted (Terminal does not show characters while typing for security) and press Return. Terminal will print:

Deleted local snapshot '2026-09-21-143022'

Repeat this command for each snapshot in the list. Once all snapshots are cleared, restart your Mac and open DaisyDisk. In most cases, 30GB to 80GB of Hidden Space will have vanished immediately.

The Safe 1-Click Solution: DiskCompanion

While the Terminal method works, it is tedious. If you have 15 snapshots accumulated over several weeks, typing dates into command lines is slow and error-prone. Furthermore, Terminal commands do not clear locked system cache buffers or resolve mysterious System Data storage bloat.

If you want visual storage exploration combined with automated, risk-free cleanup, DiskCompanion solves the problem completely.

Instead of struggling with unclickable gray wedges in DaisyDisk or wrestling with terminal commands, DiskCompanion gives you complete visibility and active control over your drive in a single native SwiftUI application.

For a full breakdown of how visualizers compare with modern cleaners, read our detailed guide on CleanMyMac vs DaisyDisk and explore our ranked list of the best DaisyDisk alternatives.