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The OS X Dock sits centered along the bottom of the screen on every Mac by default, and most users probably assume that moving the Dock to a new location is limited to centering on either the left or right side of the screen. It turns out you can actually have much more control over the Dock positioning, and with the help of a little defaults command string you can actually pin the Dock into the corner of the Mac display.
1: Place the Dock in the Desired Screen Region (Left, Right, Bottom)
First you will want to put the Dock into the general area of the screen that you want it to be. So if you want the Dock to be positioned horizontally in a bottom left or right corner, just leave it as is the default setting. If you want the Dock pinned to the corner on the left, move the Dock to the left side, and if you want the Dock to be in the right side corner, drag the Dock over there first.
The easiest way to relocate the Dock is to use the Apple menu > System Preferences option, where it will be found in the “Dock” settings panel:
You can also hold down the “Shift” key and use the resize bar to drag it to a new side of the screen, but that can be confusing for some users since it’s a bit more subtle.
2: Open Terminal and Run the Dock Defaults Command
Now you’ll need to turn to the command line to run a defaults command string. This is simple enough, so launch Terminal, found in /Applications/Utilities/, and then choose the appropriate command string from the list below. The defaults pinning command string isn’t as obvious as saying ‘top left’ so here is some general guidance on placing the Dock:
“start” = the top corners for vertical Dock positions, or the lower left corner for horizontal Dock position
“end” = the bottom corners for vertical Dock positioning, or the lower right corner for horizontal Docks
“middle” = default center positioning, regardless of a vertical or horizontal Dock configuration
Keep that in mind when choosing the Docks location using the following commands.
2a: Pin the Dock in the Top Left / Right Corner(s)
Remember to position the Dock vertically along the left or right side of the screen first to get the desired effect, then run the following defaults command string:
defaults write com.apple.dock pinning start;killall Dock
The Dock will be killed and the change will take effect instantly. Which corner the Dock sits in will depend on what side of the screen it started on (or is moved to.
For example, this is also the command to use if you want to pin the Dock horizontally in the bottom left corner, the difference is only that the Dock started at the bottom of the screen:
2b: Pin the Dock in the Bottom Left / Right Corner(s)
Again, position the Dock in the region of the screen where you want it to appear, it will be on the right side if along the bottom horizontally. The Dock will appear in lower right or left corner if it’s positioned vertically.
defaults write com.apple.dock pinning end;killall Dock
This may look like the following:
For some users it may be easier to just enter the appropriate defaults command string, and then use the “Shift+Drag” trick to relocate the Dock to the desired corner of the Mac display, which is how this is demonstrated in the brief video below:
Notice you can continue to resize the Dock regardless of it’s positioning on the screen.
Yes, this will impact where the Dock shows up on multi-display configurations running Mavericks, in other words, if you move the Dock into the bottom left corner, you will need to gesture your mouse cursor into that corner to make the Dock appear there on the secondary external display as covered here.
Return the Dock to Default Middle / Centered Position
Don’t like having the Dock sitting in a corner? Here’s how to send it back to the default centered location, regardless of location or a vertical or horizontal position:
defaults write com.apple.dock pinning middle;killall Dock
Again, the Dock will refresh automatically, and you’ll be back to the normal.
Does this only work with the Dock in OS X Mavericks?
No, you can relocate the Dock to any corner of the display in OS X versions prior to Mavericks, but you must change the defaults command string slightly so that capitalization is different. In versions of Mac OS X prior to Mavericks (Mountain Lion, Lion, Snow Leopard), use the following string instead:
defaults write com.apple.Dock pinning start;killall Dock
Notice the difference? It’s very subtle, capitalizing “com.apple.Dock” for earlier versions of OS X, while keeping it lowercase in OS X Mavericks. Otherwise everything else is the same.
Thanks to to MacFixIt for discovering this trick for earlier versions of Mac OS X.
