Your Dock is gone, stuck in place, or ignoring every click. Before you assume the Mac is broken: the Dock is just an app, and almost every "missing Dock" is one of five ordinary things. Here is what causes it and how to fix each one, fastest first.
First: is it hidden, or is it hung?
Two very different problems look identical. Hidden means the Dock slid off-screen and comes back when you move the pointer to the bottom edge. Hung means the Dock process crashed or froze, so it does not respond to clicks or reappear at all. Move your pointer to the very bottom of the screen (or the side, if you moved it there). If the Dock slides up, it is hidden and Fix 1 solves it. If nothing happens, or icons are frozen and unclickable, skip to Fix 3.
Fix 1: Turn auto-hide off (Command + Option + D)
The single most common cause. Auto-hide gets toggled on by accident with a keyboard shortcut. Press Command + Option + D to toggle it back. The Dock should snap into view and stay there.
To make it permanent: open the Apple menu, choose System Settings, click Desktop & Dock, and turn off Automatically hide and show the Dock.
Fix 2: Move your pointer to the right edge (or wherever it went)
The Dock can be set to the left or right side of the screen instead of the bottom. If the bottom edge does nothing, sweep the pointer to the left and right edges too. Found it? In System Settings > Desktop & Dock, set Position on screen back to Bottom.
Fix 3: Relaunch the Dock (killall Dock)
If the Dock is frozen, blank, or clicks do nothing, its process needs a restart. This does not touch your files, apps, or settings, it just reloads the Dock itself.
Open Terminal (in Applications > Utilities, or press Command + Space and type Terminal), then type this and press Return:
killall DockThe Dock vanishes for a second and reloads clean. This also fixes a Dock that shows the wrong icons, a stuck bouncing app, or missing spacer gaps. If Terminal will not open either, restart the Mac (Apple menu > Restart) and the Dock rebuilds on login.
Fix 4: A full-screen app is covering it
When an app is in full-screen mode, the Dock hides on purpose. If your "missing" Dock happened right after a video, game, or browser went full-screen, press Escape, or move the pointer to the top of the screen and click the green button, or press Control + Command + F to leave full screen. The Dock returns immediately.
Fix 5: It is on your other display
On a Mac with an external monitor, the Dock lives on whichever screen the pointer is on at the bottom, and it can end up on the display you are not looking at. Move your pointer to the bottom edge of your other screen. To pin it: in System Settings > Desktop & Dock, under Displays have separate Spaces and the Dock position, or simply keep the pointer on your main screen and press the bottom edge there.
Last resort: reset the Dock layout
If the Dock keeps misbehaving after all of the above, reset its saved layout. In Terminal, run:
defaults delete com.apple.dock; killall DockThis clears your custom icons and returns the Dock to the macOS default, then relaunches it. Re-add your favorite apps by dragging them from the Applications folder onto the Dock. If even a fresh Dock crashes repeatedly, that points at a deeper macOS or hardware issue, covered below.
When it is not the Dock at all
If the whole screen is frozen (not just the Dock) and the pointer will not move, that is a system freeze, not a Dock problem, and the fixes are different. See MacBook frozen? How to force quit. If the Mac is generally sluggish and the Dock is slow along with everything else, start with why your MacBook is running slow. And if the Dock and everything else breaks only after a specific update, a clean reset can help, see how to factory reset a MacBook (back up first).
Frequently asked questions
Why did my Mac Dock suddenly disappear?
Almost always auto-hide got switched on (press Command + Option + D to undo it), a full-screen app is covering it, or the Dock is set to the side or on another display. A crashed Dock process is the other common cause, fixed with killall Dock in Terminal.
What does killall Dock do? Is it safe?
It quits and instantly reloads the Dock process. It is completely safe, it does not delete files, apps, or your Dock icons, it just restarts the Dock the same way logging out and back in would. macOS relaunches it automatically within a second.
How do I get the Dock to stay visible all the time?
Open System Settings > Desktop & Dock and turn off "Automatically hide and show the Dock." That stops it sliding away when you are not pointing at it.
The Dock is frozen and clicking icons does nothing. What now?
The Dock process is hung. Open Terminal and run killall Dock to force it to reload. If Terminal will not open, restart the Mac from the Apple menu, the Dock rebuilds cleanly on login.
My Dock keeps disappearing every day. Is my MacBook failing?
Usually no, a repeating disappearing Dock is auto-hide toggling or a misbehaving app forcing full-screen, not a hardware fault. But if the Dock crashes constantly along with beachballing and freezes, that can signal a failing drive or logic board. If yours is old and struggling, a newer refurbished MacBook is often cheaper than a repair, browse the Apple clearance deals.