xbacklight

Utility to adjust backlight brightness using the RandR extension. More information: https://gitlab.freedesktop.org/xorg/app/xbacklight.

• Get the current screen brightness as a percentage:

xbacklight

• Set the screen brightness to 40%:

xbacklight -set 40

• Increase current brightness by 25%:

xbacklight -inc 25

• Decrease current brightness by 75%:

xbacklight -dec 75

• Increase backlight to 100%, over 60 seconds (value given in ms), using 60 steps:

xbacklight -set 100 -time 60000 -steps 60