How do I get Mac to show file extensions of all the files?

The Mac by default does not show file extensions. This is good in a way because most users, I assume, would not be very interested in knowing this information. Also, if the user changes the extension by mistake, it can lead to a lot of frustration because the file may become usable unless the change in the extension is reverted.

But for me, seeing the full file name with the extension is imperative. For instance, if it’s an image, I want to know if its .png, .jpg or .jpeg! I am used to identifying files by their extensions and not by their icons. (I use the List view always).

Advantages of having the Mac show you the file extension

I also believe there are certain drawbacks in not being able to view the file extension. For instance, you would not be able to decipher quickly between a png and a jpg image or an .htm from a .html.

And if you are starting on the journey of becoming a programmer or a graphic designer, I strongly suggest that you change the settings on your Mac to view the file extension.

The extension is displayed in the file information

To view the extension of a file, you can right click on it and choose “Get Info” from the menu. You can also change the file name or the extension. from the information pop-up window.

Change Finder preferences to view file extensions

Checking file extensions individually can be tedious. The best is to have the Mac Finder display the extensions of all files. Here is how you go about it.

1. Launch Finder [Slide 1].
2. Select Preferences [Slide 2].
3. Move to the Advanced tab and put a check in the “Show all filename extensions” box [Slide 3].
4. Ensure “Show warning before changing an extension” box is checked to avoid aforementioned silly mistakes [Slide 4].

That’s it! Finder will now display the extensions of all files.
Note: I’ve learnt that this change may not take effect immediately. Restarting the computer would help.