OS X: About This Mac window provides computer serial number
You can use the About This Mac window to find your computer's serial number when started up from OS X.
Follow these steps:
- Choose About This Mac from the Apple Menu.
- Double-click the version text, for example "Version 10.9".
Your computer's serial number now appears where the version text had been.
Computer serial number in the About This Mac window
Note: Some earlier OS X-compatible computers do not have their serial numbers stored in a way that allows this feature to work. Lack of this feature on your computer does not indicate any software or hardware failure.