File extension JAR

File type Compressed Archive Format Package For Java Classes And Data Format
Developer Oracle

What is JAR file?

The extension .JAR refers to files of the type Java archive files. The java archive files are run by the run-time client of java, also known as the Java virtual machine.

The archive files on the client side can be directly run using a Runtime environment known as the Java runtime Environment(JRE). The JAR packages contain classes and interfaces that have the methods defined in them to execute the program. The JAR files can be used for one of the many flavours of java applications like Standard, enterprise, mobile or light versions. Jar files are popular for games and add ons on the mobile platform.

Program(s) that can open the .JAR file


If you cannot open the JAR file on your computer - there may be several reasons. The first and most important reason (the most common) is the lack of a suitable application that supports JAR among those that are installed on your computer.

A very simple way to solve this problem is to find and download the appropriate application. The first part of the task has already been done – the software supporting the JAR file can be found below. Now just download and install the appropriate application.

This site also defines other possible causes causing the problems with JAR files.

Possible problems with the files that are in the JAR format

The inability to open and operate the JAR file does not necessarily mean that you do not have an appropriate software installed on your computer. There may be other problems that also block our ability to operate the Compressed Archive Format Package For Java Classes And Data Format file. Below is a list of possible problems.

  • Corruption of a JAR file which is being opened
  • Incorrect links to the JAR file in registry entries.
  • Accidental deletion of the description of the JAR from the Windows registry
  • Incomplete installation of an application that supports the JAR format
  • The JAR file which is being opened is infected with an undesirable malware.
  • The computer does not have enough hardware resources to cope with the opening of the JAR file.
  • Drivers of equipment used by the computer to open a JAR file are out of date.

If you are sure that all of these reasons do not exist in your case (or have already been eliminated), the JAR file should operate with your programs without any problem. If the problem with the JAR file has not been solved, it may be due to the fact that in this case there is also another rare problem with the JAR file. In this case, the only you can do is to ask for assistance of a professional staff.

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This extension
can be converted to:
How to link the file with an installed software?

If you want to associate a file with a new program (e.g. my-file.JAR) you have two ways to do it. The first and the easiest one is to right-click on the selected JAR file. From the drop-down menu select "Choose default program", then click "Browse" and find the desired program. The whole operation must be confirmed by clicking OK.

Is there a universal way to open unknown files?

Many files contain data in the form of text or numbers. It is possible that while opening unknown files (e.g. JAR) a popular Windows simple text editor, which is Notebook will allow us to see some of the data encoded in the file. This method allows you to preview the contents of many files, but probably not in such a structure as a program dedicated to support them.