v1.0 · Free · Notarized by Apple

Put every window
in its place.

SizeUp is a keyboard-driven window manager for macOS. Halves, quarters and other displays — one shortcut each. Free, native, and it lives quietly in your menu bar.

Download for macOS

macOS 13.0+ · 3.4 MB · Apple silicon & Intel · no account, no licence key

Left Half
Display 1
Display 2
Editor

Try it here. Press ⌃⌥⌘ with an arrow — or tap one:

Actions

Every position.
One keystroke.

Thirteen actions, three arrow chords' worth of muscle memory. The frontmost window of any app, moved without touching the mouse. Every binding is remappable.

SnapBack

The undo key
for your windows.

Moved a window and want it back? SnapBack restores the exact frame it had — position, size, display. Press it again to toggle forward. Window management finally has an undo.

⌃⌥⌘/
Precision

Your pixels,
your rules.

Screen-edge margins per side, gaps between tiled windows, and the split itself moved off centre. Prefer a 60/40 workday? Take it.

The preview is the engine

The Shortcuts, Margins and Partitions panes each render a live preview driven by the very same geometry code that moves your real windows. It cannot drift from the app, because it is the app — what you see is precisely where the window lands.

Every display

Send the frontmost window to the next or previous display. Turn on proportional resize and a half stays a half, whatever the resolution.

Margins & partitions

Gaps at the screen edge, gaps between windows, and the divider anywhere you want it — each toggleable, each to the pixel.

Menu bar only

No Dock icon, no window of its own. It sits in the menu bar and gets out of the way. Opens at login if you'd like.

3.4 MB of Swift

Straight onto the Accessibility API. No Electron, no helper daemon, no runtime — memory you will never notice.

Cheat sheet

Three chords. Total control.

  • ⌃⌥⌘+←↑↓→ Halves
  • ⌃⌥⇧+←↑↓→ Quarters
  • ⌃⌥+←→ Displays
  • ⌃⌥⌘+/ SnapBack
  • ⌃⌥⌘+MC Full screen · Center
SizeUp app icon

Your windows are waiting.

Every feature, no licence key, no strings.

Download SizeUp 1.0 3.4 MB · .dmg
Requires
macOS 13.0 or later
Released
2026-07-20
Signature
Developer ID · stapled
SHA-256
—

On first launch macOS asks for Accessibility permission — that is how any app is permitted to move another app's windows. SizeUp asks for nothing else, and sends nothing anywhere.