The permissions Storage Studio asks for

Storage Studio asks macOS for two permissions: Full Disk Access, so it can see and move what's using your space, and Notifications, so it can tell you when background work has finished. For a few protected changes it asks for your administrator password, and it can start at login if you want it to. You can check the live state of both permissions in Preferences → Permissions.

Full Disk Access

Why: macOS protects many folders, such as Mail, Messages, Safari and parts of your Library. Without Full Disk Access, Storage Studio can't measure them, clean caches inside them or move them. In the app's words, it "lets Storage Studio read protected folders to plan and run moves, and scan what's using space".

What it doesn't mean: the work happens on your Mac. Having Full Disk Access doesn't send anything anywhere — see What leaves your Mac.

To turn it on, see Why Storage Studio asks for Full Disk Access. If you've turned it on and the app still says it's off, see Full Disk Access is on but the app says it isn't.

Notifications

Why: so Storage Studio can tell you when something it did in the background, such as a scheduled clean-up, has run. macOS asks you the first time. You can change it any time in System Settings → Notifications.

Your administrator password

Storage Studio runs as you, not as an administrator. A few changes touch things macOS protects, so macOS shows its own password prompt. You type your password into macOS, not into Storage Studio, and Storage Studio never stores it. Typical moments are:

• moving, offloading or uninstalling an app that's owned by the system rather than by you;
• switching to a new drive when protected app shortcuts need pointing at the new drive;
• turning off Spotlight indexing on your external drive, when you agree to it;
• removing an old drive setting that stops your drive mounting at start-up.

After you approve one, macOS often lets the next few go through for a short while without asking again. If you cancel the prompt, that change isn't made.

%% caption: What happens when an action needs your administrator password
flowchart TD
  A[You start a protected change] --> B{Approved recently?}
  B -->|Yes| D[The change runs]
  B -->|No| C[macOS shows its password prompt]
  C -->|You approve| D
  C -->|You cancel| E[That change is not made]

Starting at login

Storage Studio can open when you log in, so its menu bar icon is there without you starting it. You can see and change this in System Settings → General → Login Items, or from the app — see Starting Storage Studio at login.

Things it doesn't ask for

• Camera and microphone. To keep quiet during calls (see During meetings, calls and presentations), Storage Studio only checks whether another app is using them. It never turns them on and never records.
• Accessibility. Keyboard shortcuts and the Junk Yard panel work without it.

See also: Privacy: what stays on your Mac · Full Disk Access · How Storage Studio deletes things