MonitorControl
Control external monitor brightness & volume
MonitorControl — Official Website
Quick Take: MonitorControl
MonitorControl is the best free solution for controlling external monitor brightness on macOS. It does one thing well: makes your keyboard brightness and volume keys work on external monitors via DDC/CI. It's free, open-source, lightweight, and reliable. The limitations are the limitations of DDC/CI itself—not all monitors support it, not all connections carry the signal. If you need adaptive brightness or sub-zero dimming, Lunar Pro is the paid upgrade. But for the core use case—pressing F2 to dim your external display—MonitorControl is perfect and costs nothing.
Best For
- •Anyone with an external monitor who wants keyboard brightness control
- •Users who want a free alternative to Lunar for basic DDC/CI control
- •Multi-monitor setups needing unified brightness management
- •Privacy-conscious users who prefer open-source utilities
What is MonitorControl?
MonitorControl is a free, open-source macOS app that does what Apple won't: it lets you control the brightness, contrast, and volume of external monitors using your Mac's keyboard. Press the brightness keys and your external Dell, LG, BenQ, or Samsung display dims or brightens. Press the volume keys and the monitor's built-in speakers adjust. No reaching behind the monitor, no navigating clunky OSD menus. The app works through DDC/CI (Display Data Channel Command Interface), a standard protocol that sends control commands to monitors over DisplayPort and HDMI. Most monitors from major manufacturers support DDC/CI, though some have it disabled by default in their OSD settings. When DDC/CI works, MonitorControl adjusts the monitor's actual backlight—not a software overlay—which means proper brightness control that looks natural and doesn't reduce contrast. MonitorControl sits in your menu bar and shows a slider for each connected monitor. You can adjust brightness, contrast, and volume per monitor. The keyboard brightness keys work on external displays just like they work on your MacBook's built-in screen. That's the entire pitch: it makes external monitors feel like native Mac displays. The project is open-source (MIT license) and maintained by a community of contributors on GitHub. It has over 32,000 stars, making it one of the most popular Mac utilities on GitHub. For most users who just need keyboard brightness control on external monitors, MonitorControl is all they need—no paid software required.
Install with Homebrew
brew install --cask monitorcontrolDeep Dive: MonitorControl vs Lunar — Making the Right Choice
Both apps solve the same core problem. The question is whether you need the extras.
History & Background
MonitorControl started as a simple DDC/CI brightness utility and grew into a polished open-source project. It gained popularity as the free alternative to paid tools like Lunar and BetterDisplay. The community contributions (DDC/CI fixes, UI improvements, multi-monitor support) have made it reliable for the core use case.
How It Works
MonitorControl uses Apple's IOKit framework to communicate with the GPU's I2C interface, which carries DDC/CI commands to connected monitors. The app monitors macOS keyboard events (via Accessibility API) to intercept brightness and volume key presses. Each connected monitor is queried for DDC/CI capability and controlled independently.
Ecosystem & Integrations
MonitorControl is part of the broader macOS display management ecosystem alongside Lunar and BetterDisplay. It's the entry point—free, simple, reliable. Users who need more features graduate to Lunar Pro or BetterDisplay. The three apps share the same underlying DDC/CI technology and often reference each other in their documentation.
Future Development
MonitorControl development focuses on DDC/CI compatibility improvements, macOS version updates, and UI refinements. The community-driven model means features are added based on contributor interest and user demand. Major additions are rare since the app has reached feature completeness for its scope.
Key Features
DDC/CI Brightness Control
MonitorControl sends DDC/CI commands to adjust your monitor's backlight hardware. This is real brightness control—the monitor's backlight physically changes intensity, identical to pressing the brightness buttons on the monitor itself. The result looks natural: blacks stay black, colors stay accurate, and there's no washed-out overlay effect. DDC/CI brightness works over DisplayPort and HDMI connections.
Keyboard Hotkey Integration
MonitorControl hooks into the macOS brightness and volume keys (F1/F2 for brightness, F10/F11/F12 for volume) and extends them to external monitors. When you press the brightness key, MonitorControl adjusts the external monitor alongside or instead of the built-in display. The OSD (on-screen display) slider appears just like the native macOS brightness indicator. This is the killer feature—it makes the keyboard keys work the way everyone expects.
Menu Bar Sliders
Click MonitorControl's menu bar icon and you see brightness, contrast, and volume sliders for each connected monitor. Drag a slider to adjust. The interface is minimal and clear—each monitor is labeled by name, and each has its own independent controls. For quick adjustments without keyboard shortcuts, the sliders are faster than navigating monitor OSD menus.
Contrast Control
Beyond brightness, MonitorControl can adjust contrast via DDC/CI. Most users leave contrast at the default, but it's useful for fine-tuning readability in different lighting conditions or for specific content types. Some monitors respond better to contrast adjustments than others—it depends on the monitor's DDC/CI firmware implementation.
Volume Control for Monitor Speakers
If your external monitor has built-in speakers, MonitorControl can adjust their volume via DDC/CI. Press the Mac's volume keys and the monitor speakers respond. This eliminates the need to navigate the monitor's OSD to change speaker volume—a common annoyance when using monitor speakers for video calls or background music.
Multi-Monitor Support
MonitorControl handles multiple external monitors independently. Each monitor gets its own brightness, contrast, and volume sliders. You can adjust them individually or link them so all monitors change together. For users with two or three monitors, this unified control is much faster than managing each monitor's physical buttons separately.
Software Dimming Fallback
When DDC/CI isn't available (some monitors, some connection types), MonitorControl falls back to software dimming—applying a dark overlay to reduce apparent brightness. This isn't as good as hardware DDC/CI control (it reduces contrast), but it's better than nothing for monitors that don't support the protocol.
Smooth Brightness Transitions
MonitorControl can apply brightness changes gradually instead of jumping immediately to the new value. This avoids the jarring instant-change that some monitors exhibit when DDC/CI brightness changes. The transition speed is configurable—fast for quick adjustments, slow for a more pleasant visual experience.
Who Should Use MonitorControl?
1The Developer with a Single External Monitor
You have a Dell 27-inch connected to your MacBook via USB-C. Every time the sun moves, you reach behind the monitor to adjust brightness. With MonitorControl, you press F2 on your keyboard and the Dell dims. F1 brightens it. The same keys you use for your MacBook screen now work on your external display. You never touch the monitor buttons again.
2The Multi-Monitor Professional
You have two LG monitors plus your MacBook. Each monitor currently requires separate OSD navigation to adjust brightness. With MonitorControl, all three displays are controlled from the menu bar or keyboard. When the afternoon sun hits your desk, one key press adjusts all monitors simultaneously.
3The Video Call User with Monitor Speakers
Your monitor has built-in speakers that you use for Zoom calls. Adjusting their volume requires navigating the monitor's OSD menu mid-call, which is embarrassing. MonitorControl lets you press the Mac's volume keys and the monitor speakers respond. Volume control during calls works naturally.
4The Budget-Conscious User
You need monitor brightness control but don't want to pay $23 for Lunar Pro. MonitorControl is free and handles DDC/CI brightness, contrast, and volume perfectly. If you don't need adaptive brightness, sub-zero dimming, or per-app profiles, MonitorControl gives you everything you need at no cost.
How to Install MonitorControl on Mac
MonitorControl is free and installs via Homebrew in seconds.
Install via Homebrew
Run `brew install --cask monitorcontrol` in Terminal.
Grant Accessibility Permission
On first launch, grant Accessibility permission in System Settings → Privacy & Security → Accessibility. This is required for keyboard hotkey integration.
Verify DDC/CI Support
Check MonitorControl's menu bar dropdown. If your monitor shows brightness/contrast sliders, DDC/CI is working. If it shows 'Software dimming only', your monitor or connection doesn't support DDC/CI.
Test Keyboard Keys
Press the brightness keys (F1/F2) and verify that your external monitor responds. The macOS brightness OSD should appear and the monitor's backlight should change.
Pro Tips
- • If DDC/CI doesn't work, check your monitor's OSD settings for a DDC/CI toggle—many monitors ship with it disabled.
- • Direct DisplayPort or HDMI connections work best for DDC/CI. USB-C hubs/docks sometimes strip the DDC/CI signal.
- • MonitorControl works alongside Night Shift and f.lux—they control color temperature, MonitorControl controls brightness.
Configuration Tips
Enable DDC/CI in Your Monitor's OSD
Many monitors ship with DDC/CI disabled. Navigate to your monitor's OSD menu (using the physical buttons), find the DDC/CI setting (often under 'Other' or 'System'), and enable it. Without this, MonitorControl can't send hardware brightness commands.
Try a Direct Cable Connection
If DDC/CI doesn't work through your USB-C dock, connect the monitor directly to your Mac with a USB-C to DisplayPort cable or a USB-C to HDMI cable. Docks from CalDigit and OWC generally pass DDC/CI; many cheaper docks don't.
Set Up Smooth Transitions
In MonitorControl's settings, enable smooth brightness transitions and set the speed to medium. This prevents the jarring instant-brightness-change that some monitors exhibit with DDC/CI.
Configure Keyboard Key Behavior
In settings, choose whether brightness keys control only external monitors, only the built-in display, or both. Most users want 'both' so pressing F2 dims everything. If you want independent control, set it to external monitors only and use Control Center for the built-in display.
Alternatives to MonitorControl
Monitor control on macOS has a few options:
Lunar
Lunar's free version does the same basic DDC/CI control as MonitorControl. Lunar Pro ($23) adds adaptive brightness, sub-zero dimming, per-app profiles, and schedule-based curves. If you need automation, Lunar Pro is the upgrade. If you just need keyboard brightness control, MonitorControl is enough.
BetterDisplay
BetterDisplay is a comprehensive display management tool that handles brightness, resolution, HiDPI, and display arrangement. It includes DDC/CI control plus resolution and scaling features MonitorControl doesn't have. More powerful, but also more complex.
macOS Built-in Controls
macOS only controls brightness on Apple-made displays. For any third-party monitor, you need MonitorControl, Lunar, or BetterDisplay.
Display Menu
Display Menu is a simple paid app for changing display resolution from the menu bar. It doesn't do DDC/CI brightness control. Different tool for a different purpose.
Pricing
MonitorControl is completely free and open-source under the MIT license. No paid tiers, no premium features, no ads, no donations nag screen. All features are available to everyone. The project is community-maintained on GitHub.
Pros
- ✓Free and open-source (MIT license)—no cost for full functionality
- ✓DDC/CI hardware brightness control—real backlight adjustment, not a software overlay
- ✓Keyboard brightness and volume keys work on external monitors
- ✓Clean menu bar interface with per-monitor sliders
- ✓Multi-monitor support with independent controls
- ✓Over 32,000 GitHub stars—one of the most popular Mac utilities
- ✓Software dimming fallback when DDC/CI isn't available
- ✓Smooth brightness transitions avoid jarring visual jumps
Cons
- ✗DDC/CI doesn't work with all monitors or connection types
- ✗No adaptive brightness (doesn't track ambient light like Lunar Pro)
- ✗No sub-zero dimming (can't go below hardware minimum)
- ✗No per-app brightness profiles
- ✗No schedule-based brightness automation
- ✗Some USB-C docks break DDC/CI communication
Community & Development
MonitorControl is one of the most starred Mac utilities on GitHub with over 32,000 stars. The project has an active contributor community and a responsive issue tracker. DDC/CI compatibility reports are particularly valuable—users report which monitors work and which don't, building a community knowledge base. The project accepts contributions for new features, monitor compatibility fixes, and translations. Development is ongoing with regular releases for macOS compatibility and DDC/CI improvements.
Video Tutorials
Getting Started with MonitorControl
More Tutorials
How to fix Sound and Brightness on an external display - Mac DisplayPort - Monitor Control App
J Tech WP • 19.0K views
Control your external Monitor on MacOS #mac #monitor #app #software
Alex Tech Life • 1.5K views
Controlling External Monitor Volume: How to Use eqMac with HDMI, USB-C, and DisplayPort Connections
Chris Spiegl • 33.1K views
Frequently Asked Questions about MonitorControl
Our Verdict
MonitorControl is the best free solution for controlling external monitor brightness on macOS. It does one thing well: makes your keyboard brightness and volume keys work on external monitors via DDC/CI. It's free, open-source, lightweight, and reliable. The limitations are the limitations of DDC/CI itself—not all monitors support it, not all connections carry the signal. If you need adaptive brightness or sub-zero dimming, Lunar Pro is the paid upgrade. But for the core use case—pressing F2 to dim your external display—MonitorControl is perfect and costs nothing.
About the Author
Productivity & Workflow Analyst
Related Technologies & Concepts
Related Topics
Display Management
Tools for controlling monitor brightness, contrast, and settings.
Sources & References
Key Verified Facts
- MonitorControl is a free, open-source macOS app distributed under the MIT License that allows control of external display brightness and volume using native Apple keyboard keys.[cite-1]
- The application relies on the DDC/CI (Display Data Channel Command Interface) protocol to send hardware-level commands directly to external monitors via standard video cables.[cite-2]
- Apple's official macOS documentation notes that native keyboard brightness keys typically only adjust the built-in Mac display or Apple-branded external displays, necessitating third-party utilities for third-party monitors.[cite-3]
- MonitorControl is recommended as a top utility for adding native-feeling keyboard controls to third-party external monitors, specifically highlighting its support for Dell, LG, and Samsung displays.[cite-4]
- Details how MonitorControl integrates seamlessly with macOS by displaying the native Apple OSD (On-Screen Display) overlay popups when adjusting external monitor brightness or volume.[cite-5]
- 1MonitorControl GitHub Repository
Accessed May 6, 2026
"MonitorControl is a free, open-source macOS app distributed under the MIT License that allows control of external display brightness and volume using native Apple keyboard keys."
- 2MonitorControl Wiki: How does it work?
Accessed May 6, 2026
"The application relies on the DDC/CI (Display Data Channel Command Interface) protocol to send hardware-level commands directly to external monitors via standard video cables."
- 3Change your Mac display's brightness
Accessed May 6, 2026
"Apple's official macOS documentation notes that native keyboard brightness keys typically only adjust the built-in Mac display or Apple-branded external displays, necessitating third-party utilities for third-party monitors."
- 4Best Mac apps to control external display brightness and volume
Accessed May 6, 2026
"MonitorControl is recommended as a top utility for adding native-feeling keyboard controls to third-party external monitors, specifically highlighting its support for Dell, LG, and Samsung displays."
- 5How to Control External Display Brightness From Your Mac's Keyboard
Accessed May 6, 2026
"Details how MonitorControl integrates seamlessly with macOS by displaying the native Apple OSD (On-Screen Display) overlay popups when adjusting external monitor brightness or volume."
- 6Apple Silicon (M1/M2/M3) and HDMI compatibility
Accessed May 6, 2026
"Technical analysis and benchmarks detailing DDC/CI protocol limitations on Apple Silicon Macs over HDMI connections, explaining how the app falls back to software dimming when hardware control is blocked."
- 7Homebrew Cask: monitorcontrol
Accessed May 6, 2026
"Official Homebrew package documentation showing MonitorControl's installation analytics, requirements, and version history for macOS package management."
- 8VESA Display Data Channel Command Interface Standard
Accessed May 6, 2026
"The official VESA standard definition for DDC/CI, the underlying hardware protocol MonitorControl uses to communicate brightness and volume values to external displays."
- 9MonitorControl Releases
Accessed May 6, 2026
"Release notes documenting the introduction of software dimming features for displays that do not fully support hardware DDC/CI commands, ensuring compatibility with a wider range of monitors."
- 10DDC/CI Support by Monitor Manufacturer
Accessed May 6, 2026
"Community-driven benchmark and testing data showing which specific Dell, LG, BenQ, and Samsung monitor models correctly respond to DDC/CI commands via MonitorControl without flickering."