Guide · Mac, Windows, Linux

Adjust brightness from your keyboard

Your Kuycon monitor comes with a remote. With a small free app, you can also control it from your computer: keyboard brightness keys, a slider in the menu bar, automatic dimming in the evening. Here is which app to choose, and what to do if nothing happens.

Free apps Real backlight control USB-C, DisplayPort or HDMI Keyboard keys

At a glance

Which app to install

Your computer Recommended app Price 
Mac, the simplest optionMonitorControlFree
M1 Mac connected over HDMI, or to control everythingBetterDisplayFree, optional Pro version
Mac, brightness that follows daylightLunarFree, paid automatic modes
Windows 10 or 11 PCTwinkle Tray or PowerToysFree
Linuxddcutil, or the KDE Plasma sliderFree

How it works

A control channel inside the video cable

1. You press a key or move a slider. 2. The command travels through the video cable, alongside the picture. 3. The monitor adjusts its backlight.

Current Kuycon monitors support DDC/CI (Display Data Channel / Command Interface), a VESA standard. The cable that carries the picture, whether USB-C, DisplayPort or HDMI, also carries small commands: the app asks for "brightness 70%", and the monitor adjusts its backlight, exactly as it does with the remote.

Your operating system does not use this channel on its own. On a Mac, the brightness keys only control the built-in display and Apple displays. On a PC, the Windows brightness slider targets the laptop screen. For your Kuycon monitor, you need an app that speaks DDC/CI: that is what the apps below do.

DDC/CI control

  • Changes the real backlight, just like the remote
  • Keeps the full contrast of the picture
  • Less light, so less power used

Software dimming

  • Darkens the picture without touching the backlight
  • Reduces contrast: blacks look washed out
  • Keep it as a last resort, or to go below the minimum in the evening

macOS

On a Mac

All of them work on Apple silicon and Intel Macs. Start with MonitorControl; switch to BetterDisplay if your monitor does not show up.

Simplest

MonitorControl

Free, open source

One slider per display in the menu bar and, above all, the keyboard brightness and volume keys control your Kuycon monitor, with the familiar macOS on-screen display.

  • Brightness, contrast and volume
  • macOS 11 Big Sur or later
  • macOS 27 Golden Gate: version 4.4.0 or later

BetterDisplay

Free for brightness

The most complete. DDC/CI control stays free for personal use, even after the trial, and it works on the built-in HDMI port of M1 Macs, where MonitorControl cannot.

  • Brightness, contrast, volume and input switching, free
  • Keyboard keys, free
  • Version 5: macOS 26.3 Tahoe or later, version 4.3.7 for Ventura to Sequoia

The Pro version (around €20, perpetual licence) mainly adds resolution settings. You do not need it for brightness.

Lunar

Free, Pro $23

For brightness that adjusts itself: it follows the MacBook display, the time of day or the position of the sun.

  • Manual control is free, with a daily limit on adjustments
  • Pro, lifetime licence: follows the MacBook sensor, the time or the sun, multiple displays
  • macOS 11 or later

DisplayBuddy

Paid, from $24.99

To switch between settings in one click: presets, input switching, scheduling. Also available on Windows.

  • Brightness, contrast, volume and input
  • Presets and keyboard shortcuts
  • Lifetime licence, 7-day refund
HDMI port on M1 Macs. On the built-in HDMI port of the 14-inch and 16-inch MacBook Pro with M1 Pro and M1 Max, the M1 Mac mini, the M1 Mac Studio and the entry-level M2 Mac mini, MonitorControl cannot control the monitor. Connect it over USB-C, or use BetterDisplay, which supports these ports.
For scripts. On Apple silicon Macs, the m1ddc command-line tool controls the monitor from Terminal; on Intel Macs, use ddcctl.
m1ddc set luminance 70

Windows

On a Windows PC

All of them are free and work on Windows 10 and 11.

Simplest

Twinkle Tray

Free, open source

The closest to Windows itself: one slider per display in the notification area, just like the volume slider.

  • Keyboard shortcuts for one display or all
  • Automatic adjustment by time of day or idle time
  • Microsoft Store or winget
winget install xanderfrangos.twinkletray

PowerToys Power Display

Free, by Microsoft

Microsoft's own tool, part of PowerToys: brightness, contrast, volume and input for every display in a single panel.

  • Profiles applied in one click, for example Work or Gaming
  • Keyboard shortcut, mouse wheel on the icon
  • Command line for scripts

Monitorian

Free, open source

Lightweight: one slider per display, or all displays together.

  • Adjust with the mouse wheel, touchpad or arrow keys
  • Microsoft Store
  • Keyboard shortcuts as a paid option

ControlMyMonitor

Free

For advanced users: shows and changes every DDC/CI setting of the monitor, in a window or from the command line.

  • Save and restore settings
  • No installation
  • By NirSoft
ControlMyMonitor.exe /SetValue Primary 10 70

Linux

On Linux

Everything relies on ddcutil, available in the repositories of most distributions.

ddcutil

Free, open source

The reference tool, on the command line. Code 10 is brightness, from 0 to 100 on most monitors.

sudo modprobe i2c-dev
sudo ddcutil detect
sudo ddcutil setvcp 10 70

KDE Plasma 6

Built in

Since Plasma 6.0, the brightness slider in the panel also controls the external monitor, thanks to ddcutil. Nothing else to install.

GNOME

Free extension

The "Brightness control using ddcutil" extension adds one slider per display to the system menu. For a full settings window, there is also ddcui.

Troubleshooting

Nothing happens? Five checks

Connect the monitor directly

Remove the hub, docking station or adapter. Many pass the picture through but block DDC/CI; on a Mac, DisplayLink docks never pass it on.

Try another port

USB-C and DisplayPort give the best results, HDMI is less reliable. On the HDMI port of M1 Macs and the entry-level M2 Mac mini, switch to USB-C or to BetterDisplay.

Check the monitor menu

Open the menu with the remote: if a DDC/CI option is offered, it must be turned on.

Try a second app

If MonitorControl does not see the monitor, try BetterDisplay; on Windows, Twinkle Tray then ControlMyMonitor. If none of them responds, the cause is the cable or the port, not the app.

Restart the monitor

Unplug its power for ten seconds. After an input change or sleep, a monitor can stop responding to DDC/CI commands until it is restarted.

As a last resort, the software dimming in MonitorControl or BetterDisplay works everywhere, and the remote is still there. Its batteries are not included: which batteries to buy.

FAQ

Frequently asked questions

Why don't my Mac's brightness keys change my Kuycon monitor?

macOS only applies them to the built-in display and Apple displays. MonitorControl and BetterDisplay, both free, make them work on the external monitor, with the familiar macOS on-screen display.

Do I need to install a driver?

No, neither on a Mac nor on Windows: the app is enough. On Linux, ddcutil only needs the i2c-dev module, loaded with the command sudo modprobe i2c-dev.

Does adjusting from the computer wear out the monitor?

No: the app sends the same command as the remote. Good apps only send the value after the slider pauses briefly, so they do not multiply writes to the monitor's memory.

Does it work with a USB-C hub or a docking station?

Not always. On a Mac, DisplayLink docks never pass DDC/CI on, and other hubs block it. Test by connecting the monitor directly to the computer.

Can I also adjust contrast, volume or input?

Contrast, yes, with most of the apps on this page. Volume, if the monitor has speakers or a headphone jack. Input switching is available in BetterDisplay, DisplayBuddy, PowerToys and ControlMyMonitor.

How can the monitor follow my MacBook's brightness?

MonitorControl can sync the external monitor with the built-in display, ambient light sensor included. Lunar does it too with its Sync mode, in the Pro version.

Still stuck?

Write to us with your monitor model, your computer and the cable you use: we will help you find the right setting.

Contact us

Updated on 23 October 2026. Versions checked: MonitorControl 4.4.0, BetterDisplay 5.1.1, ddcutil 3.0.1.