Is there a way I can identify the duration of an MP4 movie file on my Mac system without actually watching the movie? Get Info shows size, but not duration.
Turns out that there are quite a lot of different containers for movie files in modern operating systems, from .WAV to .AVI, .FLV to .MOV. One of the most popular – muchly due to its portability across operating systems, is MP4, known more formally as MPEG4. What’s MPEG4? I’m glad you asked! It’s the Motion Picture Experts Group 4 standard, known more formally as ” ISO/IEC 14496-14″. The good news is that you don’t really need to care. MP4 is compatible with QuickTime Player on your Mac so you won’t have any issues playing it (and if you do, I recommend Videolan’s VLC player, which can handle anything you’ll encounter on either Mac or Windows).
But back to that MP4 file. You’re right that it’s easy to get the size of the file, and since it’s a variable encoding system, there’s no easy way to calculate size versus duration: A very high quality MP4 can be huge and only 10-15 minutes long. But the Mac Finder in MacOS X 10.13 “Catalina” has some pretty cool tricks up its digital sleeve. Let’s have a look, shall we?
To start out, here’s the File > Get Info [or Command-I] information from clicking on an MP4 file’s icon:
My demo file, the 2018 Chinese action film Shadow, is a bit over 2 GB in size. But how long is the actual movie? That you don’t get amongst all the information shown.
Except you can with a single click. Simply click on the tiny grey triangle adjacent to “More Info:” and…
Not only does this show the dimensions of the image – 1920 x 800 – but it also shows the duration: 1:55:59. Just a little bit less than two hours!
There are other ways to obtain this information in the Finder too. For example, view a folder’s contents in icon view and if you have “Show Item Info” selected in the folder’s preferences window, you’ll see the duration without any work at all:
One more. Instead of double clicking to open up an MP4, remember that the Mac preview window can play movies too. So click once to select the MP4 file, then use the space bar to open up the preview and it’ll show the duration at the very lower right portion of the preview window:
Why is this different? Because I’m 13 seconds into the movie: 1:55:46 + 0:00:13 = 1:55:59.
Now you know. Hope that helps you out with your Mac Finder adventures!
Pro Tip: I’ve been writing about the Mac system for eons. Please check out my extensive Mac help area for lots more tutorials!