Both apps are free, so this comparison can’t be settled by price, and honestly it isn’t much of a fight. The two were built around different problems, and the right choice falls out of which problem is yours.
What MonitorControl does well
MonitorControl is the open-source standard, and it earned that. Its founding idea is that your keyboard’s brightness and volume keys should just work on external monitors, complete with the native-looking on-screen display Apple draws for the built-in screen. It does exactly that, and adds volume control on top, something I don’t do at all. Its own README notes one gap on macOS 26 Tahoe: the on-screen display appears, but its percentage doesn’t show or update.
It’s also fully open: MIT licensed, buildable from source, with years of monitor-compatibility lore accumulated in a public issue tracker. If you want to read the code that talks to your hardware, this is the only app in the category you can read and build in full.
And it’s considerate. Advanced options hide behind a single “show advanced settings” checkbox added explicitly to protect first-time users. I thought that was exactly right, and I copied it.
Where this app differs
MonitorControl treats displays as individuals: each gets its own slider, its own keys, its own settings. Its sync option mirrors the built-in display’s changes to your externals. Same movement everywhere.
Brightness Controller treats the set as the unit. Each display gets its own calibration line, set by your eye, in your room, and the master slider moves everyone along their own line at once, within the range where the panels can genuinely stay together. Identical percentages on different panels produce different light; matched brightness usually means different numbers, and the whole app is arranged around that fact.
There’s also the log: every adjustment this app makes is written down with its cause, so a screen that changes on its own is a question with an answer.
Choose accordingly
- Choose MonitorControl if you want brightness and volume keys with a native OSD, you value open source, or you run hardware this app doesn’t support: it works on Intel Macs, which I don’t.
- Choose Brightness Controller if your screens never quite look like each other and you want one slider that keeps them matched, including monitors that refuse brightness commands, which I dim in software so they move with the rest.
- Run both? People do. If your Mac has a built-in screen, my optional brightness-key setting moves every screen, so one app may be enough.
At a glance
| MonitorControl | Brightness Controller | |
|---|---|---|
| Price | Free | Free |
| Source | Open (MIT), buildable | Closed, public issue tracker |
| Multi-display model | Independent sliders; sync mirrors the built-in | Per-display calibration lines under one master |
| Brightness keys | Yes, its founding feature, with native OSD | Optional, on Macs with a built-in screen; macOS draws its usual OSD |
| Volume control | Yes | No |
| Adaptive | Follows the built-in display | Ambient-sensor auto-follow along calibrated lines |
| Explains itself | No | Plain-text log of every change and its cause |
| Intel Macs | Yes | No: Apple Silicon, macOS 14+ |
Facts checked September 2026; both apps move quickly, so check their sites for current details.