Control external monitor brightness from your Mac
macOS's brightness keys usually don't work on third-party monitors. Display Control talks to supported monitors over DDC to change brightness, contrast and speaker volume from your Mac. For displays that don't support DDC, it can dim the picture in software instead.
How to use Display Control
Open Display Control to see your connected displays.
Drag the brightness, contrast or volume sliders for a monitor.
Click Refresh if you just plugged in a display.
Turn on Restore these settings when Toolbox opens to keep your levels.
Questions about Display Control
Why can't I change my external monitor's brightness on Mac?
macOS only controls brightness on Apple displays and a few others. Most monitors need DDC commands, which Display Control sends for you.
What is DDC?
DDC/CI is a standard that lets a computer adjust a monitor's settings over the video cable. Some monitors turn it off by default or don't support it over certain adapters and docks.
What happens if my monitor doesn't support DDC?
Display Control falls back to software dimming, which darkens the picture on screen. It can't change the backlight, so contrast and volume aren't available.
Related tools
- Presentation ModeOne switch before you share your screen: hide desktop icons, hide the Dock and stay awake.
- Keep AwakeStop your Mac from sleeping during downloads, renders or talks, for as long as you choose.
- Mouse FixesScroll your mouse and trackpad in different directions, and make the mouse wheel faster or smooth.
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