blight

Set display brightness to a percentage

$ blight set [50] -r

$ blight show

$ blight max

$ blight inc [number] -r

$ blight dec [number]

blight command [value] [options]

blight adjusts display brightness on Linux systems. It can set brightness to absolute values or relative percentages, and supports incrementing and decrementing brightness levels.
The tool interfaces with the kernel's backlight subsystem to control display brightness.

-r, --relative

Interpret value as percentage (0-100)

set value

Set brightness to specified value

Display current brightness level

Print maximum brightness value

Increase brightness by value

Decrease brightness by value

Requires appropriate permissions to access backlight controls. May need to run as root or configure udev rules for unprivileged access. Only works with displays that expose backlight control through sysfs.

backlight_control(1), xbacklight(1), brightnessctl(1)