How to Customise Your Mac Dock: What System Settings Actually Lets You Do (and Where It Stops)

macOS gives you exactly one slider to customise the Dock — icon size — plus a handful of toggles for position, auto-hide, and Magnification. That's the complete list. If what you want goes beyond those controls (different icon spacing, folders, per-monitor docks, themes), you'll need either a terminal command or a third-party app.

What System Settings actually lets you change

Open System Settings → Desktop & Dock and you'll find:

• Size — a slider that sets icon size roughly between 16px and 128px
• Magnification — hover zoom, with a second slider for the magnified size
• Position on screen — Left, Bottom, or Right (applies to your main display only)
• Minimise windows using — Genie effect or Scale effect
• Automatically hide and show the Dock — one toggle, no speed or delay control
• Show suggested and recent applications — toggles the Recent Apps section
• Show indicators for open applications — the dot beneath running apps
• Show items in full-screen spaces — whether the dock peeks in during full-screen

That's it. No spacing control, no theme options, no per-monitor behaviour, no folders, no icon grouping.

What terminal commands can do (and their limits)

A few hidden defaults exist that go slightly further. These work on macOS Sonoma and Sequoia, but Apple can remove them at any point without warning.

Add a blank spacer tile to the Dock:

bash defaults write com.apple.dock persistent-apps -array-add '{"tile-type"="spacer-tile";}' killall Dock

This inserts an invisible gap you can drag around like a normal icon — useful for grouping apps visually.

Speed up the auto-hide animation:

bash defaults write com.apple.dock autohide-time-modifier -float 0.15 killall Dock

The default is around 0.5 seconds. Setting it to 0 removes the animation entirely; 0.15 feels snappy without looking abrupt.

Remove the auto-hide delay (the pause before the dock appears):

bash defaults write com.apple.dock autohide-delay -float 0 killall Dock

To restore any of these defaults:

bash defaults delete com.apple.dock autohide-time-modifier defaults delete com.apple.dock autohide-delay killall Dock

What terminal cannot do: change the dock's visual theme, show it on multiple monitors simultaneously, create app folders, or give you live window previews on hover. Those require a different approach.

Where the dock genuinely stops working for multi-monitor setups

The single biggest frustration I hear from people with two or three monitors is this: the macOS Dock only ever appears on one screen at a time. It floats to whichever display your cursor is on (after a brief hover at the screen edge), which means constant mouse trips across monitors just to launch an app.

There is no System Settings toggle to change this. It is a hard architectural limitation of the macOS Dock — it was designed for a single display, and that design hasn't been revisited in any meaningful way.

What a dock replacement can do that macOS can't

If the native limits are blocking you, Dockish is worth a look. It replaces the macOS Dock entirely (with a one-click option to hide the system dock) and fills in the gaps System Settings leaves:

• Dock on every monitor — independent or mirrored layouts per display, with hot-plug support when you connect or disconnect screens
• iPhone-style app folders — drag one app onto another to group them, with a 2×2 preview grid and auto-naming; useful if your dock has grown to 30+ icons
• Icon size 24–96px with adjustable spacing — actual numeric control, not a vague slider
• Themes — glass, dark, light, or a custom tint colour
• Magnification at 120Hz — smooth spring animations that match ProMotion displays
• Live window previews on hover — see what's open before you click, with the option to close windows straight from the preview
• Smart click behaviour — clicking a minimised app restores it correctly, rather than bouncing you to a minimised thumbnail
• Rich right-click menus — Chrome profile switching, media controls, Force Quit with Option held — plus context menus for Brave, Edge, Arc, iTerm2, Ghostty, and more

It's a one-time purchase at $6.99 with a 7-day free trial, so you can test it against your actual setup before committing. Version 1.1 also shipped with one-click import of your existing macOS Dock apps, so you don't have to rebuild from scratch.

Should you bother with a third-party dock at all?

Honestly — it depends what's bothering you.

If you just want a spacer between groups of apps, the terminal command above takes 30 seconds and costs nothing. If auto-hide feels sluggish, the animation defaults fix that instantly.

But if you're working across two or more monitors and the mouse trip to the dock is a genuine daily irritation, or your dock is so cluttered you're clicking the wrong app three times a day, the native customisation ceiling is real and there's no workaround for it short of a replacement.

For users who want to stay free, DockDoor is worth knowing about — it adds hover window previews to the stock macOS Dock without replacing it. It's a narrower tool but a solid one if that's the only thing missing for you.

Common questions

Can you change the Mac dock icon size to an exact pixel value?

macOS only exposes a slider with no numeric input — you can't type in a specific pixel value. Dockish lets you set icon size from 24px to 96px with a numeric field, which is useful if you want consistent sizing across displays.

How do you get the Mac dock to show on all monitors?

macOS cannot show the dock on multiple monitors simultaneously — it moves to whichever screen your cursor is near. The only way to have a persistent dock on every display is with a third-party replacement like Dockish, which supports independent or mirrored dock layouts per monitor.

How do you make the Mac dock auto-hide faster?

Run defaults write com.apple.dock autohide-time-modifier -float 0.15 in Terminal, then killall Dock. This shortens the slide animation to 0.15 seconds. To also eliminate the hover delay before the dock appears, run defaults write com.apple.dock autohide-delay -float 0 and killall Dock again.