How to Run JAR File: Step-by-Step Guide

JAR (Java Archive) files bundle Java applications for easy distribution. But if you’re new to Java, running these files can be confusing—especially if double-clicking the JAR doesn’t work. In this guide, you’ll learn two foolproof methods to execute JAR files: using the command line and a batch script.

Method 1: Run JAR File via Command Line

The simplest way to run a JAR file is using the java -jar command. Here’s how:

Step 1: Verify Java Installation

First, ensure Java is installed on your system. Open Command Prompt (Windows) or Terminal (macOS/Linux) and run:

java -version

If the single hyphon – does not work then use double hyphon:

java --version

If either command shows the output like below:

openjdk 17.0.5 2022-10-18 LTS
OpenJDK Runtime Environment Corretto-17.0.5.8.1 (build 17.0.5+8-LTS)
OpenJDK 64-Bit Server VM Corretto-17.0.5.8.1 (build 17.0.5+8-LTS, mixed mode, sharing)

Note: If you have installed the other version of the JDK then you may see the different output.

If Java is not installed, then you can visit our guide to Install and Set Up Java Development Environment.

Step 2: Run the JAR File

1. Navigate to the folder containing your JAR file using the cd command:

cd C:\path\to\jar\directory  

1. Execute the JAR file with:

java -jar yourfile.jar  

1. Replace yourfile.jar with your JAR’s actual name.

Troubleshooting Tips

• “Java is not recognized”: Add Java to your system’s PATH variable.
• “No main manifest attribute”: The JAR lacks a main class definition. Rebuild it with an entry point specified.

Method 2: Run JAR File Using a Batch Script

Batch files automate repetitive tasks. Create a batch script to run your JAR file with one click:

Step 1: Create the Batch File

1. Open Notepad and paste this code:

@echo off  
java -jar "C:\path\to\yourfile.jar"  
pause  

1. Replace the path with your JAR’s actual location.
2. Save the file as run_jar.bat (select “All Files” as the type).

Note

The batch and bat words are used to refer same thing. The only difference is that, batch is the file format that holds some command to do some action and the bat is the extension of the batch file.

Note:

If you are creating the bat file using notepad then make sure to select Save as type: All. If you don’t do this, even you give the file name HelloWorld.bat it still saves the file as a text document.

Step 2: Run the Batch File

Double-click the run_jar.bat file. The JAR will execute, and the Command Prompt will stay open to display output/errors.

Pro Tip: Add the batch file to your desktop or taskbar for quick access.

Conclusion

You’ve now learned two reliable ways to run JAR file:

1. Command Line: Use java -jar yourfile.jar for quick execution.
2. Batch File: Automate the process with a one-click script.

For more Java tips, check out our guides on creating executable JARs and fixing common Java errors.