To change the default app for a file type on your Mac, select a representative file in Finder, open File > Get Info, expand Open with, choose an app, then click Change All. That choice applies to files of the same type; choosing an app from Open With on a file only opens that file once. (Apple Support: Choose an app to open a file on Mac)

Set the default app for a file type

  1. In Finder, locate a file with the extension you want to change, such as .jpg or .pdf.
  2. Select the file and press Command-I, or choose File > Get Info.
  3. In the Info window, click the disclosure arrow beside Open with.
  4. Open the app menu and select your preferred app.
  5. Click Change All, then confirm if macOS asks you to do so.

Apple documents this as the way to change the app used to open all files of a particular type. The crucial step is Change All: if you only want to open the selected file in a different app, stop after selecting an app in Open with and do not apply the change to all matching files. (Apple Support: Choose an app to open a file on Mac)

For example, if you want JPEG images to open in a photo editor by default, select a .jpg file and make the change there. To make a different choice for another file type, such as .png, repeat the process with a .png file. This gives you a practical check: confirm the selected example file has the extension for the group you intend to affect before clicking Change All.

Choose between a one-time choice and a lasting default

Use Open With when you need another app for just one occasion: in Finder, Control-click a file, choose Open With, and select an app. You can also select the file and use File > Open With. Apple lists these as ways to open a file once with a specific app. (Apple Support: Choose an app to open a file on Mac)

Use Get Info > Open with > Change All when you want macOS to use the selected app for that file type in future. In other words, the decision depends on whether your preference applies only to this file or to files of its type generally.

Check the file type before changing the setting

A filename extension—the characters after the final period, such as .jpg—identifies a file type and can help you choose the right sample file. macOS may hide extensions, though, so you might not see them in Finder. Apple notes that hidden extensions do not prevent macOS from opening files with the proper apps. (Apple Support: Show or hide filename extensions on Mac)

To reveal extensions, choose Finder > Settings, click Advanced, and select Show all filename extensions. Or select an individual file, choose File > Get Info, expand Name & Extension, and clear Hide extension. These controls show the extension; they do not change which app opens the file. (Apple Support: Show or hide filename extensions on Mac)

Avoid renaming an extension as a way to change the default app. The extension identifies the file type, and changing it can stop the file from opening properly. To change a file’s format, Apple advises using an app that can convert it; choosing the default app is a separate action. (Apple Support: Show or hide filename extensions on Mac)

If the app you want is missing or the file still will not open

First, check whether the app is installed and can open that format. If the app appears in the Open with menu, select it and apply Change All. If the file still fails to open, the issue may be that the file is damaged or the app does not recognize it; Apple recommends trying another app. (Apple Support: Choose an app to open a file on Mac)

If the result is unexpected, reopen Get Info on a file of the intended type and inspect the Open with selection. Make sure you chose the correct extension and clicked Change All. Finder’s extension display can help you identify the file type, but it does not confirm that a file’s contents are valid or compatible with a particular app.

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