How to change the default apps used to open files in macOS

Changing from the default apps to others acquired from the Mac App Store or elsewhere can be useful for those using macOS in a working capacity. For example, a web developer may want to open text files in Panic's Coda, while a photographer could prefer for images to open in Pixelmator or another tool instead of the standard Preview.

Email

If you want to change your Mac's email client from the default Mail, the option is available within Apple's own app.

Open Mail, then select the Mail menu option, then Preferences to bring up a settings window.

Under the first General tab, the top item is a dropdown box labeled Default email reader. Open the dropdown and select your chosen email reader.

If it is not on the list, click Select and use the following window to find the app, then click Select.

Close the settings window and the Mail app.

Web browser

By default, Safari is set as the browser that will open for web links, but unlike Mail, the setting is actually buried within System Preferences.

Click the Apple logo in the Menu then System Preferences. Select General, which is the top left-most icon in the System Preferences window.

Towards the lower half of the General window is a dropdown box labeled Default web browser. Click the dropdown box, select the browser you want to use instead of Safari, and close the window.

Note that, unlike changing the email client, there is no option to manually select the browser if it is not on this dropdown box list.

Apps that open files

In macOS, you can change what app opens a specific file type from the file itself. Right-click a file that you want to change the default app that opens, and select Get Info.

In the Get Info window for the file, expand the Open With section by clicking the side arrow to bring up a dropdown box listing apps. Use this box to select the app you want to use.

If the app is not listed, select Other to bring up a new window to find the application manually. If the app isn't installed at all, there is the App Store option to download it from there, or you can download it from somewhere else online and start the process again.

Once satisfied with the alteration, select Change All. In the following window warning about the permanent change, select Continue, then close the Get Info window.

Changing the app for just one file.

If there is one specific file that needs to be regularly opened in a different app to the default, but all others don't need to be changed, this can be accomplished using a similar process.

Follow the instructions in the "Apps that open files" section, but stop before selecting Change All. At this point, this file is set up to open using the alternative app, and the window can be closed without further changes.

A temporary alternative

It is worth remembering that it is possible to open alternative apps on an occasional basis without going through the trouble of changing defaults.

If you right-click a file and select Open With, a list of apps macOS thinks will work with it will be created, which can be used to open the alternative app for this particular instance. If the app isn't available, click Other to find the app you want to use.