Arranging windows
4 min read
Mochi can move and resize the windows of your other apps: half the screen, a third, a quarter, the whole display, or the display next door. There are two ways to do it — a shortcut that acts on whatever window is in front, and a search you type when you want to arrange several apps at once.
Turn on the shortcuts
Open Settings > Hotkeys
Scroll to the Window snapping group.
Turn on the switch beside the group
All of the shortcuts below become active straight away. Turning it off releases them again, so another app can have them back.
Grant Accessibility if you have not already
Moving another app's window needs the Accessibility permission, the same one the snippets and writing tools use. See Permissions.
The shortcuts
These act on the window that is in front, in whatever app that is.
Left half
Right half
Top half
Bottom half
Top left quarter
Top right quarter
Bottom left quarter
Bottom right quarter
Left third
Middle third
Right third
Fill the display
Centre the window
Make it a step bigger
Make it a step smaller
Put it back where it was
Move it to the next display
Move it to the previous display
You can change any of them in Settings > Hotkeys, the same way as every other shortcut.
Press again for a different width
Pressing the same shortcut twice in a row cycles through the sensible widths for that edge, so you do not need a separate shortcut for each one. A second press has to land within about a second; after that it counts as a fresh instruction and applies the first size again.
| Shortcut | First press | Again | Again |
|---|---|---|---|
| ⌃⌥← | Left half | Left third | Left two thirds |
| ⌃⌥→ | Right half | Right third | Right two thirds |
| ⌃⌥D / ⌃⌥G | A third | Two thirds | — |
| ⌃⌥↩ | The whole display | Almost the whole display | — |
Arrange several apps at once
Open the search window and type arrange, followed by the apps you want, separated by +. Mochi lists the layouts that fit however many apps you named, each with a small picture of where the windows will go. Press ↩ on the one you want.
arrange safariLayouts for one app: halves, thirds, quarters, centred, filled
arrange safari + notesSide by side, stacked, or 60/40
arrange safari + notes + mailThree columns, or one big window with two stacked beside it
Working across two displays
- Every zone is worked out for the display the window is currently on, so ⌃⌥← fills the left half of that screen rather than of some other one.
- Moving a window to another display keeps its proportions rather than its measurements. A window filling the left half of a large monitor fills the left half of the laptop it moves to, instead of hanging off the edge.
- Windows are always kept fully on screen. Growing one that already fills the display does nothing rather than pushing its title bar under the menu bar.
- Where a window was before its first snap is forgotten when you plug in or unplug a display, because that place may no longer exist.
When a window will not move
- Check that Settings > Hotkeys > Window snapping is switched on. The shortcuts do nothing at all until it is.
- Check that Mochi is ticked in System Settings > Privacy & Security > Accessibility.
- Some windows cannot be resized by any app — the built-in About windows, most preference sheets, and anything that is currently full-screen. Mochi leaves full-screen first where it can.
- If a shortcut does nothing anywhere, another app may already have claimed it. Settings > Hotkeys says so when macOS refuses one.