A plist file stores settings and data for Mac and iOS apps in a structured format

Plist stands for "property list." It is a file format that Mac and iOS apps use to save preferences, configuration data, and other information. When you change a setting in an app — like your email address, window size, or theme preference — the app often saves that choice to a plist file so it remembers your preference the next time you open it.

Plist files are plain text or binary (compressed) files that organize data in a structured way. They live in specific folders on your Mac, usually hidden from view in your user Library. You will not normally need to open or edit a plist file yourself, but understanding what they are helps when troubleshooting app problems or when you see one mentioned in support instructions.

Key Takeaways

  • Plist files store app settings and preferences so apps remember your choices between sessions.
  • Most plist files are located in your user Library folder, which is hidden by default on Mac.
  • You can view and edit plist files using the Property List Editor app or a text editor, but changing the wrong setting can break an app.
  • Deleting a plist file resets an app to its default settings, which sometimes fixes problems when an app crashes or behaves oddly.
  • Plist files use a specific structure with keys and values that apps rely on to read the data correctly.

Where plist files live on your Mac

Plist files are stored in the Library folder inside your user account. On Mac, this folder is hidden by default because it contains system and app data that most people do not need to access. To see your Library folder, open Finder, click the Go menu at the top, hold down the Option key, and select Library. You will see a folder called Preferences — this is where most app plist files live.

The file names usually follow a pattern like com.companyname.appname.plist. For example, a plist file for Apple Mail might be named com.apple.mail.plist. Some apps store multiple plist files, and some store data in other formats alongside plist files. The exact location and number of files varies by app.

What information a plist file contains

A plist file holds whatever data the app developer decided to store there. Common examples include window position and size, font choices, color schemes, login information, notification settings, and recently opened files. Some apps store almost all their settings in a plist; others use plist files for only a few preferences and store the rest elsewhere.

The structure of a plist file uses keys and values. A key is the name of a setting (like "WindowWidth"), and the value is what you set it to (like "800"). The app reads these pairs and applies them when it starts. If a key is missing or the value is corrupted, the app uses a default value instead.

How to view a plist file

If you need to look at a plist file, you have a few options. The easiest is to use Property List Editor, which comes built into Mac. Open Finder, navigate to Applications, then Utilities, and double-click Property List Editor. Click File, then Open, and navigate to the plist file you want to view. The editor will display the keys and values in a readable format.

You can also open a plist file with a text editor like TextEdit or a code editor like Visual Studio Code. Plain-text plist files (usually older ones) will display as readable text. Binary plist files will show as garbled characters because they are compressed. If you see gibberish, the file is binary and you should use Property List Editor instead.

Resetting an app by deleting its plist file

If an app crashes repeatedly, freezes, or behaves strangely, deleting its plist file sometimes fixes the problem. Deleting the file does not remove the app itself — it only erases the stored settings. The next time you open the app, it will create a new plist file with default settings, and you will need to reconfigure your preferences.

To delete a plist file, navigate to the Preferences folder (using the Finder method described above), find the file for the app that is causing problems, and drag it to the Trash. Empty the Trash, then restart the app. If the problem was caused by corrupted settings, the app should work normally now. If the problem persists, the issue is likely something else, and deleting the plist file will not help.

Before you delete a plist file, consider backing it up first. Drag the file to your Desktop or another folder so you have a copy. If resetting the app does not solve the problem, you can put the original file back.

When you might need to edit a plist file

Most of the time, you should not edit a plist file directly. Apps are designed to manage their own plist files, and changing the wrong value can cause the app to crash or behave unpredictably. However, some advanced troubleshooting steps or app-specific workarounds require editing a plist file by hand.

If you are following support instructions that tell you to edit a plist file, use Property List Editor rather than a text editor. Property List Editor understands the plist structure and will not let you accidentally create invalid syntax. Always make a backup copy of the file before you edit it. If something goes wrong, you can restore the original and try again.

The difference between plist and other file formats

Apps on Mac and iOS use plist files because they are simple, reliable, and built into the operating system. Other systems use different formats: Windows apps often use the Registry or .ini files, and web apps typically use JSON or databases. Plist files are specific to Apple systems, which is why you will only encounter them on Mac, iPad, or iPhone.

Some modern Mac apps have moved away from plist files and use other storage methods like SQLite databases or JSON files. However, plist files remain the standard for many built-in Apple apps and older third-party apps. If you use a Mac, you will likely encounter plist files at some point, especially if you troubleshoot app problems.

Frequently Asked Questions

Is it safe to delete a plist file?

Yes, deleting a plist file is safe. It only removes the app's stored settings, not the app itself. The app will create a new plist file with default settings the next time you open it. You will lose your preferences, but the app will function normally.

Can I edit a plist file with TextEdit?

You can open a plain-text plist file with TextEdit, but it is not recommended. If you make a syntax error, the app may not read the file correctly. Use Property List Editor instead, which prevents syntax errors and is designed for this purpose.

Why are plist files hidden on Mac?

Apple hides the Library folder and its contents because most users do not need to access them. Hiding these files prevents accidental deletion or modification that could break apps or system functions. You can unhide the Library folder temporarily whenever you need it.

What does the .plist file extension mean?

The .plist extension stands for "property list." It tells your Mac that the file contains structured data in Apple's property list format. Some plist files do not have a visible extension, but the system still recognizes them as plist files based on their content.

Do iOS apps use plist files?

Yes, iOS apps use plist files to store preferences and settings, just like Mac apps. However, you cannot access the Library folder on an iPhone or iPad the way you can on a Mac. iOS keeps app data private and hidden from the user.