How to see total uptime on a mac Back when I had a Windows machine I used a program called CrystalDiskInfo to see total hours of operation of my computer. I only used the numbers for fun or to like indicate how "used" my PC was.. 

So I'm looking for a terminal command or an app that can display that information for me.

Screenshot of the crystaldiskinfo gui.
The command you want is called uptime:

|ruby-2.1.2| cortana in ~
○ → uptime
14:49  up 3 days, 21:51, 4 users, load averages: 1.41 1.32 1.30


From the man page:


  The uptime utility displays the current time, the length of time the system has been up, the number of users, and the load average of the system over the last 1, 5, and 15 minutes.