What is WindowServer on Mac?
By Junaid, maker of Taskglass · Last reviewed
Draws every window, menu and animation you see on screen, and routes your clicks and keystrokes.
WindowServer is the macOS display server. Apps draw their own content, and WindowServer combines it into the final picture on each display, handles moving windows and animations, and sends mouse and keyboard input to the right app. It runs whenever you're logged in, and its activity rises with how much is changing on screen. Some CPU use is completely normal, especially with several or high-resolution displays.
- Category
- macOS system
- Made by
- Apple
- Safe to quit:
- No
Shown in Activity Monitor as WindowServer
Why is WindowServer using so much CPU or memory?
- Many open windows, or apps that redraw constantly (animated web pages, video, games)
- Several or high-resolution external displays, especially at scaled resolutions
- Transparency and motion effects, Stage Manager, or many desktops with live content
- Screen recording, screen sharing or video calls capturing the screen
- One misbehaving app flooding the screen with updates
What to do
- 1Close windows and browser tabs you don't need, especially ones playing video or animation
- 2Quit apps one at a time and watch whether WindowServer drops, to find the trigger
- 3Turn on Reduce transparency and Reduce motion in System Settings > Accessibility > Display
- 4Try your external display at its default resolution, or disconnect it to compare
- 5Restart your Mac if it stays high with only a few windows open
Safe to quit? No.
Force quitting WindowServer instantly logs you out and closes all your apps, so unsaved work is lost.
Typical usage
Rough ranges on Apple Silicon Macs. Yours will vary.
- CPU
- 2–15% when idle; 20–60% with lots happening on screen
- Memory
- 200 MB – 2 GB; more with several or high-resolution displays
Related guides
Related processes
- kernel_taskThe core of macOS itself. It also holds busy apps back on purpose to stop your Mac overheating.
- DockRuns the Dock, plus Mission Control, Spaces (multiple desktops), App Exposé and Hot Corners.
- WindowManagerPowers Stage Manager and related window-management features.
- loginwindowHandles logging in and out, the lock screen, and keeps your user session running.
Part of the Taskglass Process Library