Dimmerly

Dimmerly is a native macOS menu bar app for display brightness, warmth, contrast, presets, schedules, and display sleep.

It is mainly built for external-monitor setups where the useful controls are either buried in the monitor OSD or split across System Settings. On supported external displays, Dimmerly can use DDC/CI for hardware brightness and monitor controls. When DDC/CI is not available, it falls back to software dimming.

Features

• Per-display brightness, warmth, contrast, and blanking controls
• Built-in display support where macOS exposes the needed controls
• Presets for saving and restoring complete display setups
• Global keyboard shortcuts for dimming and presets
• Schedules based on a fixed time, sunrise, or sunset
• Desktop widgets and Shortcuts actions
• Optional automatic color temperature changes
• Optional auto-dim after inactivity
• Direct-download build: display sleep through macOS tools
• Direct-download build: DDC/CI hardware brightness, contrast, volume, mute, and input switching
• App Store build: sandbox-compatible software dimming and screen blanking
• VoiceOver labels and Reduce Motion support
• Local settings only; no analytics, tracking, or app-managed network requests

Requirements

• macOS 15 Sequoia or later
• Optional Accessibility permission for global shortcuts
• Optional Location permission for sunrise and sunset schedules
• Optional DDC/CI-capable external monitor for hardware controls

Install

Homebrew

brew tap olujicz/dimmerly
brew install --cask dimmerly

The Homebrew cask installs the signed and notarized direct-download build with the full feature set.

Direct Download

Download the latest signed and notarized DMG from GitHub Releases.

This build has the full feature set, including display sleep, DDC/CI hardware control, monitor input switching, and hardware volume controls where the display and connection support them.

App Store Build

The repository also includes a sandboxed App Store configuration. Because that build runs inside Apple's sandbox, it uses software dimming and screen blanking instead of DDC/CI or system display sleep.

Build From Source

See BUILDING.md for Xcode requirements, build configurations, test commands, and architecture notes.

Build Differences

Capability	Direct download	App Store build
Per-display brightness, warmth, and contrast	Yes	Yes
Presets, schedules, widgets, Shortcuts	Yes	Yes
Display sleep using macOS system tools	Yes	No
DDC/CI hardware monitor control	Yes	No
Monitor input switching	Yes	No
Hardware monitor volume and mute	Yes	No
App Sandbox	No	Yes

Use the direct-download build if you want the hardware monitor controls. Use the sandboxed build when App Store distribution or sandboxing matters more.

Screenshots

Usage

Menu Bar Controls

Open Dimmerly from the menu bar to adjust each display. The main slider controls brightness. Expand a display row for warmth, contrast, and, when available, DDC/CI controls such as volume or input source.

If a display shows the hardware indicator, Dimmerly is talking to it through DDC/CI. Otherwise the app uses software dimming for that display.

Presets And Schedules

Presets save the current display setup: brightness, warmth, and contrast for each display. They can be applied from the menu bar, widgets, Shortcuts, schedules, or per-preset keyboard shortcuts.

Schedules can run at a fixed time, at sunrise, at sunset, or with an offset from sunrise or sunset. Sunrise and sunset schedules can use your current location or manually entered coordinates.

Dimming And Wake Behavior

The direct-download build can put displays to sleep. Dim-only mode keeps the session visible but darkened, which is useful when you want quick wake behavior without display sleep.

Wake behavior can be configured for:

• keyboard, click, scroll, or mouse movement
• keyboard, click, or scroll when mouse movement is ignored
• Escape only for stricter dismissal

Animated transitions respect the macOS Reduce Motion setting.

Automation

Dimmerly includes Shortcuts actions for setting brightness, warmth, and contrast, sleeping displays, toggling dimming, and applying presets.

It also includes small and medium desktop widgets for quick dimming and preset access.

Known Limitations

• Hardware monitor controls require a DDC/CI-capable display and connection. Some hubs, docks, KVMs, HDMI adapters, DisplayLink adapters, and built-in HDMI ports can block DDC/CI commands even when the monitor supports them.
• Monitor support varies by manufacturer and model. Some displays expose only brightness, while others also expose contrast, volume, mute, or input switching.
• The direct-download and Homebrew builds include display sleep and DDC/CI hardware controls. The App Store build is sandboxed, so it uses software dimming and screen blanking instead.
• Global keyboard shortcuts require Accessibility permission from macOS.
• Sunrise and sunset schedules need Location permission unless you enter a manual coordinate.
• Dimmerly stores settings locally and does not sync presets or schedules between Macs.

Privacy

Dimmerly does not collect analytics, usage data, crash reports, or personal data.

Settings are stored locally with UserDefaults. If you use current location for sunrise and sunset schedules, macOS Location Services provides the coordinate used for the calculation. Dimmerly does not send that coordinate to a developer-owned service.

Read the full Privacy Policy.

Troubleshooting

Brightness Does Not Change The Monitor Backlight

If a display does not show the hardware indicator, Dimmerly is using software dimming for that display. Software dimming changes perceived brightness, not the monitor backlight.

Common reasons DDC/CI is unavailable:

• the monitor does not support DDC/CI
• DDC/CI is disabled in the monitor's on-screen menu
• a USB-C hub, dock, KVM, HDMI adapter, or DisplayLink adapter blocks DDC commands
• the display is connected through built-in HDMI on some Apple Silicon Macs

Try connecting the monitor directly over USB-C or DisplayPort and check the monitor's settings for DDC/CI support.

Keyboard Shortcuts Do Not Work

Global shortcuts require Accessibility permission:

System Settings -> Privacy & Security -> Accessibility

After granting permission, restart Dimmerly. If the shortcut still does not work, choose a shortcut that is not already reserved by macOS or another app.

Displays Wake Too Easily

Open Settings and adjust the dimming wake behavior. Enable "Ignore mouse movement" if small pointer movement wakes the displays, or enable Escape-only dismissal for stricter control.

Development

Dimmerly is a Swift 6 macOS project with a single third-party runtime dependency: MenuBarExtraAccess (MIT). See NOTICES.md for its license text.

Useful commands:

just setup
just format-check
just lint
just test
just build-release

Project documentation:

• BUILDING.md - local build, test, and architecture notes
• documentation/RELEASE.md - release process for signed and notarized builds
• documentation/REPOSITORY_SETTINGS.md - required GitHub repository settings
• SECURITY.md - supported versions and vulnerability reporting

Contributing

Bug reports, focused fixes, and well-scoped feature proposals are welcome.

Before opening a pull request:

1. Run just setup once to enable the local pre-commit hooks.
2. Keep changes focused.
3. Add or update tests for behavior changes.
4. Run just format-check, just lint, and just test.
5. Update CHANGELOG.md when the change affects users.

Read CONTRIBUTING.md and CODE_OF_CONDUCT.md before participating.

Security vulnerabilities should not be reported in public issues. Follow SECURITY.md.

License

Dimmerly is released under the MIT License. See LICENSE. Third-party software notices are listed in NOTICES.md.