How to see your Mac’s Reboot History

To check your Mac’s reboot history, run this command in your Terminal:

reboot

The Terminal will output the dates of the last three times your Mac was restarted. Here’s my Terminal output:

reboot    ~                         Tue Sep 15 13:03
reboot    ~                         Fri Sep 11 15:55
reboot    ~                         Fri Sep 11 13:29

How is knowing your Mac’s reboot history valuable?

Well, the older your Mac or any computer is, the more often it requires a reboot to flush its RAM and other temporary data that is clogging up the system and hurting its performance.

If your Terminal output says you haven’t rebooted your Mac in several days, it’s probably time to do it, especially if your Mac is 2+ years old.