How Much Has That Mac Been Used?
This is obviously only of use on a MacBook (including Pro/Air), but the number of times a battery has been charged is useful information. This is represented as the charge cycle figure. A low charge cycle figure on an older Mac means one of two things: either the Mac hasn’t been used much or – and perhaps more likely – the Mac has spent most of its life attached to its charger, so might rarely have left the owner’s home or office. Either way, a low number is good news.
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This figure is approximately the number of hours the drive has been powered-up since it was installed in the computer.
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If the user you’re buying the Mac from has never reinstalled macOS/OS X then you can find out exactly when they first powered-up the Mac and completed the initial setup. Just open a Terminal window as described above and paste in the following:
ls -l /var/db/.AppleSetupDone