Lumo

External monitor brightness, input & darkroom — from one menu bar icon.

Free & open-source (MIT)Apple Silicon · macOS 13+under 1 MB

Download View on GitHub

What it does

Brightness

Control the hardware backlight of external monitors over DDC/CI — including USB-C and HDMI displays.

Input switching

Change a monitor's input source from the menu bar, like a software KVM for a shared display.

Darkroom

Dim and warm any screen — including the built-in display — for a per-display night mode. Works even without DDC.

Why Lumo?

	Lumo	MonitorControl	Lunar / BetterDisplay
Price	Free (MIT)	Free	Freemium / paid
Footprint	< 1 MB	~25 MB	30 MB+
Input switching	Yes	No	Pro
Per-display darkroom	Yes	No	Yes
Settings window	None	Yes	Extensive

Sizes approximate. Want a deep, configurable tool? Use Lunar or BetterDisplay. Want brightness + input + a night dimmer in a sub-1 MB app with zero config? That's Lumo.

Install

Requires an Apple Silicon Mac on macOS 13 (Ventura) or later.

# Homebrew
brew install --cask yokihara/tap/lumo

# or grab the DMG from Releases and drag Lumo.app into Applications