Reader Murray Freiman takes some time to ask about the time a Mac takes. He writes:
I am a member of a Mac Computer Club at a retirement facility. We maintain a site with five computers. We wish to determine the number of hours each computer is used. Is there an app internal to the Mac to accomplish this? If not, is there a a downloadable program with a resettable clock that will accomplish this?
If you’re interested simply in knowing how long a Mac has been on (and would like to flex a little geek muscle in the process) it’s easy to do. Just launch Terminal (found in the Utilities folder inside the Applications folder at the root level of your hard drive) and when you see the prompt, enter
uptime and press Return.
Terminal will respond with something like
12:37 up 4 days, 3:54, 2 users, load averages: 0.24 0.19 0.20
That breaks down this way: Current time, number of days, hours:minutes, number of accounts using the computer during that time, and load average over the last 1, 5, and 15 minutes.
If you’re averse to Terminal, you’re welcome to download Joakim Nygård’s free ShowOff Widget, that puts this information in a handy widget. iSlayer’s free iStat Pro is another widget that can display this information (along with a wealth of other helpful information about your Mac).
If you’d like to know how long particular users have been logged into a Mac, you can use Terminal for that as well. Launch Terminal, enter
last, and press Return. Terminal will display a list of accounts that have been/are logged into the Mac. If the account has been logged out, you’ll see both the login and logout date and time along with the amount of time the account was logged in. If the account is still logged in, you’ll see the date and time when it first logged in.