← Hammerdeck

Window management for an ultrawide monitor on Mac

What macOS gives you

Since macOS 15 Sequoia: drag a window to a screen edge to tile it, the Window › Move & Resize menu, and keyboard shortcuts for halves (fn ⌃ plus an arrow key), fill, centre, and arranging two windows side by side. Quarters exist but ship without a shortcut. There are no thirds and no grid.

A grid on one key

Hammerdeck's Window Grid is on from the first launch. Press a grid key and the screen shows numbered cells; press a cell and the focused window fills it. Press a second cell, below and to the right of the first, and the window spans everything between them.

• ⌃⌥⌘6 — a 6-cell grid: 3 across by 2 down on a wide screen. Cells 1 then 4 give you the left third, full height.
• ⌃⌥⌘9 — 3×3, for finer pieces.
• ⌃⌥⌘4 — 2×2.
• ⌃⌥⌘Z — undo the last placement.

Three windows into three pieces of an ultrawide, in six key presses, then one key undoes the last.

See every window at once

The other ultrawide problem is the reverse: twelve windows on one huge screen, half of them buried. Two features answer it, both on by default:

• Window Deck (⌃⌥⌘K) lists the windows on the screen; tick the ones you want and they tile into an even grid. Click one and it becomes a large centred window with the rest peeking behind; the same key puts every window back where it was.
• Window Fan (⌃⌥⌘F) spreads the windows against the screen edges so each keeps a strip no other window can cover. Click any strip to switch to it.

Window Deck on an ultrawide: eight windows tiled, one brought forward at a time, then everything restored.

Halves, corners and fine adjustment

The everyday moves are there too: ⌃⌥⌘ with an arrow key snaps to a half, ⌃⌥⌘↩ toggles between full size and a centred 75%, and ⌃⌥⌘W enters a keyboard mode where single keys move, resize and nudge the window until you press Escape. You can also save any rectangle you like and give it its own key. Every shortcut can be changed in Settings.

Using more than one display as well? See moving windows between displays and putting them back when a monitor reconnects.

Other apps

Rectangle (free, open source) has keys for thirds, fourths, sixths, eighths and ninths, and drag-to-edge snapping. Moom ($15) has a resize grid and saved layouts. The comparison page has the details.