- You need to open your Terminal. Either by going to your Applications>Utilities>Terminal or by simply using Spotlight Search (type Command + Space on your keyboard) then type Terminal and press enter.
- Type the below command into your Terminal and press enter:
system_profiler SPHardwareDataType
The Terminal will display your serial number as shown below:

This command in macOS will also show you more details about your machine. These include Model, Chip, Memory, Total number of cores and more.
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