Want to know how long you have been standing 🙂 – and it works without problems! – Apple OS? No problem – a simple Terminal team will help you.
♥ BY TOPIC: Active angles on macOS: what it is, how to set up and use it.
How to find out the date macOS was last reinstalled on your Mac
1. Launch the Terminal application. You can find it through the Spotlight search (the icon with a magnifying glass in the upper right corner of the screen, next to the clock) or through Launchpad → Other.
2. Copy (⌘Cmd + C) and insert (⌘Cmd + V) to the Terminal window the following command:
ls -l /var/db/.AppleSetupDone
3. Press the key Return (Enter).
A date line will appear in the Terminal window: for example, June 3, 2014.
Please note: this information is not affected by the installation of minor macOS updates; only data on “clean” installations are taken into account (“from scratch”).
♥ BY TOPIC: How to reinstall macOS or restore Mac factory settings.
That is, if you installed macOS Mojave on top of macOS High Sierra, the Terminal will not inform you about this update. Accordingly, if the Mac seller “did not take a steam bath” with a complete reinstallation of macOS, then you will quickly understand if he is telling the truth or cheating.
By the way, when buying a laptop, it will not be superfluous to check the number of battery recharge cycles. Recall this, you can do this: Apple menu ( “apple” in the upper left corner of the screen) → About this Mas → System report → Power supply → Number of recharge cycles.