A sleek, native SwiftUI macOS application designed for real-time monitoring and manual/automated control of MacBook fan speeds. Compatible with both Intel and Apple Silicon (M1/M2/M3/M4/M5+) architectures.
It features a dual-component design: a sandboxed SwiftUI GUI front-end that communicates with a privileged command-line helper (smc-helper) to securely read and write System Management Controller (SMC) registers.
- Real-Time RPM Monitor: Displays actual fan speeds with a custom rotating vector fan blade animation that responds to changes in RPM.
- Auto-Trigger Rules Engine: Set custom, automated temperature rules for CPU, GPU, or Battery (e.g., if CPU ≥ 75°C, override all fans to 80%). Multiple active rules are evaluated dynamically, prioritizing the highest safety speed, and automatically returning control to macOS once the sensors cool down.
- Manual Mode Controls: Precise target speed adjustment sliders.
- Quick Presets: Set speed thresholds instantly using the Min, 20%, 50%, 80%, or Max buttons.
- Linked Fan Tuning: Option to sync adjustments across all system fans simultaneously.
- System Metrics: Monitors battery and sensor temperatures alongside active speed states.
- Safety Mode: Instantly yields control back to macOS automatic management when closed or reset.
The codebase is organized into clean, single-responsibility files conforming to MVVM patterns:
- 📂
Core/: Core drivers (SMC.swift) managing the raw AppleSMC register reads/writes and Silicon unlocking sequences. - 📂
Models/: Shared structs (FanJSON.swift) describing deserialized telemetry packages and auto-rules. - 📂
ViewModels/: Orchestration logic (FanViewModel.swift) querying sensors, checking authorization, persisting rules, and evaluating automatic triggers. - 📂
Views/: Reusable SwiftUI layout pieces.SpinningFanView.swift: Animated vector fan widget.TempMetricCard.swift: Temperature telemetry indicators.FanControlRow.swift: Single-fan state picking and speed slider row.RulesEngineView.swift: Dynamic rules addition board.ContentView.swift: Window layout coordinator.
- 📂
App/: Application Entry Scene (FanControlApp.swift) coordinating regular activation and system Menu Bar Extra tray access. - 📂
Helper/: Privilege operations wrapper (main.swift) serving as a setuid execution client.
- Operating System: macOS 13.0 Ventura or newer.
- Build Tools: Swift compiler (installed via Xcode or Xcode Command Line Tools).
Clone the repository and run the automated packager script inside the project directory:
# Make the build script executable
chmod +x build.sh
# Compile and package the application bundle
./build.shThis compiles smc-helper and FanControl, drafts the app metadata (Info.plist), and processes the visual assets to output a standard application bundle: Fan Control.app.
By default, the build script pins the app and helper binaries to macOS 13.0 and creates a Universal 2 bundle for both Intel and Apple Silicon Macs. You can override those defaults when needed:
MACOS_DEPLOYMENT_TARGET=14.0 ARCHS="arm64" ./build.sh-
Launch the Application: Open the application bundle in Finder or launch it from your terminal:
open "Fan Control.app" -
Configure Privilege Setup (Required Once): Writing custom values to the SMC requires administrative permission. On the first launch, follow these steps to configure access:
- Click the orange "Authorize & Enable Fan Adjustments" button in the app window.
- Enter your macOS administrator password when prompted.
Alternatively, you can manually set the privileged helper permissions using the command-line:
sudo chown root:wheel "Fan Control.app/Contents/MacOS/smc-helper" sudo chmod +s "Fan Control.app/Contents/MacOS/smc-helper"
To return your fans to macOS automatic controller management:
- Select Auto in the mode picker for individual fans.
- Click the "Reset All to Auto" button at the top/bottom of the window.
- Closing the application will also automatically release manual control overrides.
This project is open-source software licensed under the MIT License.