SizeUp
SizeUp is a lightweight macOS window management utility that lets you resize, reposition and snap windows into predefined layouts using keyboard shortcuts. It sits in the menu bar and uses the system Accessibility framework to control window positioning, making it popular with power users who want to maximize screen real estate and work efficiently without dragging windows manually. SizeUp has been a long-standing utility for productivity-focused Mac users since the late 2000s.
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1 suggestionSizeUp has been discontinued by its developer, Irradiated Software. The last release was version 1.7.4, published in 2018, and the app is Intel-only with no native Apple Silicon build. Although it still runs under Rosetta 2 today, it will stop launching entirely when Apple removes Rosetta in macOS 28 (September 2028). A viable native replacement is Rectangle, a free and open-source window management utility that mirrors SizeUp's keyboard-driven workflow. Rectangle is actively maintained, runs natively on Apple Silicon, and can import SizeUp-style keyboard shortcuts during setup, making the transition straightforward. If you prefer a commercial option with additional layout templates, Magnet is available on the Mac App Store and also runs natively on Apple Silicon.
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