Make your Mac screen brighter or dimmer

Why it happens

Your Mac sets screen brightness in a few places that all do the same job. The keys are quickest, Control Center is handy if your keyboard has no brightness keys, and Displays settings holds the slider plus the automatic brightness switch.

How to fix it

1. Press F1 to dim the screen and F2 to brighten it. They're the keys with small sun symbols near the top left of the keyboard. On a MacBook Pro with a Touch Bar, use the brightness button in the Touch Bar instead.

2. Or click Control Center in the menu bar (the icon with two small switches) and drag the Display slider left or right.

3. For the full settings, open System Settings, click Displays and drag Brightness. This is also where you'll find the switch for automatic brightness.

   Displays›Brightness

4. Want finer steps? Hold Shift and Option while you press F1 or F2, and the brightness moves in quarter steps.

Still not fixed?

1. If brightness keeps changing by itself, turn off Automatically adjust brightness in Displays.

   Displays›Automatically adjust brightness

2. If F1 and F2 don't change brightness, hold fn while you press them. Your keys may be set to work as standard function keys.

3. On an external monitor, use the monitor's own buttons. Apple displays are the exception and use the Brightness slider in Displays.

4. If the screen looks dim and yellow, Night Shift may be on. Check it in Displays.

   Displays›Night Shift…

5. If the screen stays very dark even at full brightness, the backlight may have a fault. That's hardware, so contact Apple Support or a repair shop.