How can I dim a monitor below its lowest hardware brightness?

Enable software dimming alongside hardware brightness, then use Combined brightness to adjust both with one slider. A monitor’s lowest hardware setting can still be visibly bright. Software dimming darkens the image further without requiring the monitor to lower its backlight beyond that limit.

  1. Open Settings > Displays > [display] > Device Control and keep a working hardware-brightness controller enabled. For a compatible external monitor, this is commonly Brightness (hardware) under DDC Control.
  2. Enable Enable software-based video adjustments in the display’s Image Adjustments section.
  3. Enable Combined brightness and test the main brightness slider. With both paths working, the lower part of its range adds software dimming after the configured hardware minimum is reached.

Combined brightness manages the hardware and software parts of the range together. If another app is also changing brightness, quit that app while checking the setup so its adjustments do not compete with BetterDisplay.

If software dimming works but hardware brightness does not, check the DDC connection and enabled controller separately. Combined brightness needs both hardware and software brightness controllers to be available. Software dimming can also work on its own. In that case, the monitor’s own brightness number stays unchanged.

See why brightness percentages differ for the combined scale and Device Control for the software-dimming switchover point. Software dimming changes the image rather than lowering the backlight further. The software brightness value does not measure light output or power consumption.

To keep hardware brightness above a chosen floor while still dimming the image, open the display’s Image Adjustments > Image Adjustment Settings… and set Combined brightness - minimum allowed hardware brightness level. This Pro setting uses the hardware controller’s own percentage scale. Below that level, the combined slider keeps hardware brightness at the floor and uses software dimming. This setting does not measure flicker. Choose and test a hardware level suitable for your monitor.