SuperdockHow to add spacers between Dock icons
Short answer. Run defaults write com.apple.dock persistent-apps -array-add '{"tile-type"="spacer-tile";}' then killall Dock. A blank gap appears at the end of the Dock and you drag it where you want. Repeat for more. To remove one, drag it out of the Dock like any icon. Use small-spacer-tile for a narrower gap.
The command
Open Terminal and run these two lines together:
defaults write com.apple.dock persistent-apps -array-add '{"tile-type"="spacer-tile";}'
killall DockA blank space appears at the right end of the application section. Drag it to wherever you want the gap. Run the command again for each additional spacer.
What each part does
defaults writechanges a preference value.com.apple.dockis the Dock's preference domain.persistent-appsis the list of items in the left section, the pinned applications.-array-addappends to that list rather than replacing it, which is the important part. Without it you would wipe your Dock.killall Dockrestarts the Dock so it reloads its preferences. Your windows and apps are unaffected.
Worth knowing what you are pasting. A command that writes to persistent-apps without -array-add will replace every pinned app you have.
Variants
A narrower gap: use small-spacer-tile instead of spacer-tile.
A gap in the right section, where folders and the Trash live, uses persistent-others in place of persistent-apps.
defaults write com.apple.dock persistent-others -array-add '{"tile-type"="spacer-tile";}'
killall DockRemoving a spacer
Drag it out of the Dock and hold until Remove appears, exactly as you would with an app icon. There is no separate command needed.
What this does not give you
Apple's Dock has no visible divider, only blank space. There is no line, no colour, and no way to label a group. The spacer is also invisible, so it can be fiddly to grab when you want to move it later.
A dock replacement that draws its own tiles can offer real dividers, fixed-width spacers and flexible spacers that push groups apart, configured in a settings window rather than in Terminal. That is a reason to replace the Dock, not a reason to avoid the command above, which is free and works today.
Frequently asked questions
Will this break my Dock?
No, as long as you include -array-add. That appends a spacer rather than replacing the list. Without it, the command overwrites every pinned app.
Do spacers survive a restart?
Yes. They are stored in the Dock's preferences like any other item.
Why can I not see the spacer I just added?
It is transparent, and it lands at the right end of the applications section. Look for a gap before the divider line, then drag from there.
Is there a way to do this without Terminal?
Not with Apple's Dock. Several dock replacements offer spacers and dividers in their settings, which is the only way to avoid the command line here.
Download free Superdock is free to download. The dock, window previews, the switcher and multi-display support are all free. Chrome profile icons: 14 days free, then $7.99 once. macOS 14 or later.
Continue reading
Independent macOS developer and the author of Superdock. I switched to a Mac from Windows, lost the per profile taskbar buttons I relied on, and built the dock I wanted instead. I write these guides from daily use of the apps in them, and I answer the support email myself.