How to Configure an External Display on macOS

- Difficulty
- Beginner
- Tested on
- macOS Sequoia 15.0 - MacBook Pro M3
- You will need
- USB-C or HDMI cable, External monitor
Step by step
Establish the physical connection
Plug the video cable into the appropriate port on your external monitor and your Mac. If your Mac lacks a native HDMI or DisplayPort connection, insert a compatible USB-C multiport adapter or Thunderbolt dock first. Power on the monitor to ensure the display detects the signal.
Note: Ensure your monitor is set to the correct input source using the physical buttons on the device.Open Display settings
Click the Apple menu in the top-left corner of your screen and select System Settings. Navigate to the Displays tab in the sidebar. Your connected external monitor will appear in the main pane.
Arrange your display layout
Click the Arrange button to define the physical orientation of your monitors. Drag the blue rectangles to match the actual physical placement of your screens on your desk. This ensures the mouse cursor moves fluidly between the two displays.
Note: The small white bar on the rectangle represents your primary menu bar.Configure resolution and refresh rate
Select your external display within the Display settings menu. Choose Default for display to allow macOS to determine the optimal resolution, or select Scaled to manually adjust text size and workspace area. Scroll down to the Refresh Rate menu and select the highest available hertz for fluid motion.
Note: Higher refresh rates require a high-quality cable, such as a certified Thunderbolt 4 or Ultra High Speed HDMI 2.1 cable.Choose mirror or extend mode
Locate the Use as menu in your display settings. Select Extended display to use the monitor as a separate workspace, or Mirror for [Display Name] to show the exact contents of your Mac screen on the external monitor.