2 file types use the .properties file extension.

What is a PROPERTIES file?

A PROPERTIES file is a settings file used by Minecraft, a sandbox block construction game. It stores configuration information for the game in the Java Properties key-value pair plain text format, which also has applications outside of Minecraft. In Minecraft, gamers may use PROPERTIES files when configuring a multiplayer server or a game mod.

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Common PROPERTIES Filenames

How to open a PROPERTIES file

Category: Game Files

Java Properties File

A PROPERTIES file may also be a text-based configuration file used by Java applications to store data as simple key–value pairs. Java programs load these files using the java.util.Properties API (or the closely related ResourceBundle API), allowing applications to read settings such as preferences, file paths, feature flags, or user-facing text. Each line typically follows the format key = value , making the files easy to edit and maintain.

In addition to configuration data, PROPERTIES files are commonly used for localization and translation in Java applications. In this role, each file represents a specific language or locale, such as Bundle.properties (default language) and Bundle_sl.properties (Slovenian). The keys remain the same across languages, while the values contain translated text shown in the app's interface. Many PROPERTIES files use Unicode escape sequences (for example, \u0161 ) to represent non-ASCII characters, a long-standing convention that ensures compatibility across Java versions and tools.

Unlike some configuration systems, Java does not automatically persist PROPERTIES files to a fixed directory or convert them into nested folders. Where and how a PROPERTIES file is stored depends entirely on the application, often alongside the program files, inside a .JAR or ZIP-based installer, or within a project's resources directory. Developers access and manage these files directly through the java.util.Properties or ResourceBundle APIs, giving full control over loading, saving, and updating property values.

You can open PROPERTIES files with source code editors, such as Microsoft Visual Studio Code , Sublime Text , or Notepad++ . Any plain text editor will open PROPERTIES files, as well, including Microsoft Notepad , Apple TextEdit , and gedit .

When editing a PROPERTIES file, it is important to preserve the key = value structure and avoid removing escape sequences like \uXXXX , which represent Unicode characters. Also, while editors can view and edit PROPERTIES files, they are typically intended to be loaded and managed by Java applications rather than opened directly by end users.

Programs that open or reference PROPERTIES files

Updated: December 18, 2025