How to snap windows on a Mac

macOS has some built-in tiling, and there are good apps for the rest. Here's how each approach works — and when a custom-zone app earns its place.

1. The built-in options

Recent versions of macOS can tile windows: drag a window to a screen edge, or use the Window menu, to fill half or a quarter of the screen. Split View and Stage Manager also help arrange a couple of windows. These are great for a quick two-window split, but they stop short of custom layouts and precise sizing.

2. Keyboard snappers

Apps like Rectangle (free) and Magnet snap the active window to halves, thirds, and quarters with keyboard shortcuts. If your layout is a simple grid of equal regions, these are fast and dependable.

3. Custom drag-to-snap zones

When your layout isn't a clean half or quarter — say a browser taking the left three-quarters with a chat and a terminal stacked on the right — a zone-based tool fits better. Screen Divider lets you build that grid once in a visual editor, merge cells into the exact zones you want, and then drag any window in. An overlay shows where it will land; releasing snaps and resizes it.

Setting it up with Screen Divider

• Install the app and grant Accessibility access when macOS asks (every window manager needs this).
• Open Edit Layouts from the menu bar and split the screen into the regions you use.
• Select adjacent cells and Merge them into a single zone.
• Drag any window toward a zone and let go — it snaps and resizes to fill it.

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