What permissions it needs
Rectangle App requests one permission: Accessibility access (System Settings → Privacy & Security → Accessibility). This is required for any third-party tool that moves or resizes windows belonging to other apps.
Accessibility access lets Rectangle:
- Read which window is currently active (frontmost)
- Read that window's current position and size
- Set that window's new position and size
That is all. Rectangle does not read window content, does not access the pasteboard, does not connect to the internet, and does not log keystrokes.
Open source trust
Rectangle is open source under the MIT licence. The full source code is publicly available and has been reviewed by many developers. If you want to verify exactly what the app does, you can read the code or compile it yourself from source.
This is a meaningful trust advantage over closed-source alternatives like Magnet or Moom. You are not taking the developer's word for what the app does — you can verify it.
Privacy
Rectangle does not have network access built in. It does not phone home, send telemetry, or require an account. The only data it writes to disk is your preferences stored in ~/Library/Preferences/com.knollsoft.Rectangle.plist.
For privacy-conscious users, Rectangle App is one of the safest productivity tools you can install: open source, offline, and scoped to the minimum necessary permissions.
Frequently asked questions
Can Rectangle see my passwords or clipboard?
No — Accessibility permission does not grant access to clipboard contents, passwords, or window content. Rectangle only sees and modifies window frame (position and size) data.
Does Rectangle phone home or collect data?
No — Rectangle has no network permission requirements and does not send telemetry. The app is entirely offline.
Is the Rectangle App on the Mac App Store?
Rectangle (free) is distributed outside the App Store via direct download. Rectangle Pro is available on the Mac App Store. Both versions are notarised by Apple, meaning Apple has scanned them for known malware.