The MacBook is equipped with a sensor that detects the opening and closing angle of the display.

Apple's MacBook has a hinge equipped with a sensor that detects the angle at which the display is opened and closed, according to engineer Sam Henry Gold .

sam henri gold (@samhenrigold) / X
https://x.com/samhenrigold

According to Gold, starting with the 16-inch MacBook Pro released in 2019, the hinge that opens and closes the display has been equipped with a sensor that detects the angle.

The 'display angle' detected by this sensor is not available as a public API, but Gold found a way to read the sensor data and used it to create an application that displays the display angle, as shown in the video below.

Did you know your MacBook has a sensor that knows the exact angle of the screen hinge?

It's not exposed as a public API, but I figured out a way to read it and make it sound like an old wooden door. pic.twitter.com/qysTbr9TV4

— sam henri gold (@samhenrigold) September 6, 2025

Gold has released LidAngleSensor, an app that shows the opening and closing angle of a MacBook's display, on GitHub. However, there have been reports that LidAngleSensor doesn't work on M1-equipped MacBooks, and no solution has been found at the time of writing. Gold is testing LidAngleSensor on an M4-equipped MacBook Pro.

GitHub - samhenrigold/LidAngleSensor: tfw when you when your lid when uhh angle your lid sensor
https://github.com/samhenrigold/LidAngleSensor

According to Apple's repair guidelines, replacing the hinge angle sensor is required when replacing the display. The hinge angle sensor can be replaced separately, but in either case, you'll need to boot the system from the configuration. If you don't replace the hinge angle sensor, strange issues with waking and waking the MacBook will occur.