How to Change Default Applications in macOS

When you double-click a file on your Mac, macOS automatically determines which application should be used to open it based on the file’s extension. For example, macOS will universally open all .jpg files in the Preview app, and all .txt files in TextEdit. However, if you recently installed a professional photo editor like Adobe Photoshop or a robust text editor like Sublime Text, you likely want those new applications to handle your files instead. You can easily instruct macOS to change the default application associated with any file type.

How to Change the Default App for a Specific File Extension

To change the default application, you do not need to dive into system settings. You perform the change directly on a file of the type you want to modify.

1. Open the Finder and locate a file that has the extension you want to change (e.g., locate any .pdf file on your desktop).
2. Right-click (or Control-click) on the file.
3. From the context menu, select Get Info. (Alternatively, click the file once to highlight it and press Command + I).
4. A long, vertical information window will appear. Look about halfway down for a section labeled Open with:.
5. Click the small arrow next to “Open with:” if the section is currently collapsed.
6. Click the drop-down menu that currently displays the default application (e.g., Preview) and select your preferred new application (e.g., Adobe Acrobat Reader).

How to Apply the Change Universally

If you stop at the previous step, macOS will only open that one specific file in Acrobat Reader. All other PDFs on your computer will still open in Preview. To make the change universal, you must complete one final step.

1. Immediately below the “Open with:” drop-down menu, click the button labeled Change All….
2. A security prompt will appear asking: “Are you sure you want to change all similar documents to open with the application [App Name]?”
3. Click the blue Continue button to confirm.

From this moment forward, every single .pdf file across your entire Mac will automatically open in Adobe Acrobat when double-clicked.

How to Force an App to Open a File Once

If you usually want your images to open in Preview, but you have one specific image you need to edit in Photoshop right now, do not change the default settings.

1. Right-click the specific file.
2. Hover your mouse over Open With (do not click “Get Info”).
3. A secondary menu will slide out showing all installed apps capable of reading that file type.
4. Click on Photoshop. The image will open in Photoshop this one time, but Preview will remain the permanent default application for the future.