Free, open-source display control for macOS (Apple Silicon). Control your external monitor's real hardware — brightness, contrast, volume, colour, input source — over DDC/CI, from the menu bar, your keyboard, the CLI, or Apple Shortcuts. An open alternative if you're weighing tools like BetterDisplay, Lunar, or MonitorControl.
Install (30 seconds)
- Download
OpenDisplay.zipbelow and unzip. - Drag OpenDisplay.app to Applications and open it — signed & notarized, no Gatekeeper warnings.
- Click the display glyph in the menu bar. Done.
Optional: turn on media keys in Settings so your keyboard's brightness keys drive the external monitor's actual backlight (one-time Accessibility grant — the app arms itself the moment you grant it).
What's new in 0.3.0
⌨️ Keyboard media keys + native-style OSD
Press F1/F2 and your external monitor's real backlight changes over DDC/CI — with macOS-style steps, ⇧⌥ fine control, and a native-looking on-screen HUD. Choose the target: display under cursor, main display, or built-in.
🖥️ DDC engine rebuilt to work with any monitor
- Displays matched to their control channel by EDID identity (vendor/model/serial), not port order — correct on docks, mixed HDMI/DisplayPort, and identical twin monitors.
- Reads recover replies other tools miss: checksum-validated frame scanning tolerates desynchronized and quirky panels.
- Fully serialized I2C transactions — concurrent slider drags can't corrupt the bus.
- Fast menus: features your monitor doesn't support are remembered, not re-probed on every open.
🎛️ More hardware controls
Sharpness and red/green/blue gain sliders appear automatically on monitors that support them. Power users: opendisplay ddc <display> vcp 0xNN [value] reads/writes any MCCS feature code.
Also
- Automatic hardware rediscovery when a monitor comes back (port switch, power-cycle) — no restart.
- Software-dim and Black Out interactions fixed (no double-dimmed or surprise-lit panels).
- 240 unit tests (up from 192); hardware paths verified live on Apple Silicon.
Full details in the CHANGELOG.
Requirements: Apple Silicon Mac, macOS 14+.