How to see how long an app has been open on a Mac

4 October 2026 · 6 min read

Open Terminal and run ps -axo etime,lstart,comm | grep -i "Notes.app", with the name of your app in place of Notes. The first column is how long the app has been running and the next is the exact date and time it was launched. That answers “how long has it been open.” It does not answer “how long did I use it,” which is a different number and needs a different tool; both are covered below.

The one-line answer in Terminal

1. Open Terminal (in Applications, Utilities).
2. Type the following, replacing Notes with the app you care about, and press Return:

ps -axo etime,lstart,comm | grep -i "Notes.app"

3. Read the line that ends in the app’s own name.

The output looks like this:

03-04:12:09 Thu Oct  1 09:41:22 2026     /System/Applications/Notes.app/Contents/MacOS/Notes

What the columns mean:

• etime is elapsed time since launch, written as days, hours, minutes and seconds. 03-04:12:09 is three days, four hours and twelve minutes. With no days it is just 04:12:09, and under an hour it is 12:09.
• lstart is the full launch date and time.
• comm is the path of the program, which is how you tell which line is which.

Some apps print several lines, because they run helper processes alongside the main one. The main app is the line whose path ends with the app’s name. Helpers usually started at the same moment, so the numbers agree anyway.

See every open app at once

To list everything that lives inside an app bundle, with its running time:

ps -axo etime,comm | grep "\.app/Contents/MacOS/"

The list is long, because macOS itself runs many background pieces that are packaged as apps. Scan for the names you recognize. An entry showing many days has been open since you last restarted the Mac or last quit that app, whichever is more recent.

Why Activity Monitor does not quite answer it

Activity Monitor is the obvious place to look, and it has a column called CPU Time that seems promising. It is not the same thing. CPU Time is how much processor time the app has consumed, so an app that has been open for a week and mostly idle might show a few minutes.

You can add and remove columns under View, Columns, and you will find memory, energy, threads and more. For time since launch, the ps command above is the direct route.

How long the Mac itself has been up

Apps that open at login have been running about as long as the Mac has. To check that:

uptime

It prints how long since the last startup. The same figure appears in System Information (hold Option and choose it from the Apple menu) under Software, as “Time since boot.”

If you are trying to work out when your day started rather than when the Mac did, How to see what time you started using your Mac today is the better guide, since a Mac that only sleeps at night has an uptime of weeks.

Open, in front, and in use are three different numbers

This is where most people’s real question is hiding. “How long has it been open” can mean three things.

Running. The time since launch. This is what ps reports. It includes every hour the app sat behind other windows and every night the Mac was asleep. A mail app that has been open for twelve days has not had twelve days of your attention.

In front. The time the app was the frontmost one, the app whose name is next to the Apple menu. This is much smaller and much closer to what you mean by “used.”

In use. The time you were really doing something in it. No tool knows this exactly. An editor can be in front for an hour while you stare out of the window.

Running time is the right number when you are diagnosing: an app that has grown slow or is using a lot of memory after weeks without a quit, for example. Quitting and reopening it resets the clock and often the problem.

For anything about your own time, you want the second number.

Seeing time in front, per day

macOS has one built-in view of this. Open System Settings, Screen Time, App & Website Activity, and it shows usage per app for a day or a week. It covers the whole day including evenings, and it has no export button.

Punchcard answers the same question for the workday. It sits in the menu bar and notices which app is in front as you go. At the closing time you set, it prints a paper receipt: one line per app with the time on each (the top five, with the rest as MISC) and a day total. If you want the detail, its CSV export has one row per session with a start, an end, the app and the seconds, so you can see each separate stretch an app spent in front, not just the sum.

What it does not do is worth saying plainly. It does not report when an app was launched or how long it has been running; that is the ps command’s job. An app working away behind another window (a long export, music playing) gets no time while something else is in front. And it records app names only, with site names if you switch on itemized browsing: never window titles, document names or anything typed. That is why it needs no Accessibility or Screen Recording permission.

Tracking is free and does not expire, and the first two receipts are free. Printing after that needs the license, $9 once.

For more on why the two numbers differ so much, see The difference between time spent and time worked. For how the Mac chooses the app in front, see How macOS decides which app is frontmost.

Questions

Does quitting and reopening an app reset the time?

Yes. etime counts from the most recent launch. Closing an app’s window is not the same as quitting, though. Many Mac apps keep running with no windows open, and the clock keeps going until you choose Quit.

Does the time include hours the Mac was asleep?

Yes. It is simply the gap between the launch time and now, so nights with the lid closed are counted. That is one more reason running time says little about use.

Can I see when an app was open on a previous day?

Not with ps, which only knows about what is running now. How to see when an app was last opened on a Mac covers the traces macOS keeps for apps that are no longer open.

Is there a way to do this without Terminal?

For time since launch, Terminal is the direct way. For time in front, Screen Time or a receipt gives you the figure without typing anything.