---
title: ".jar file — what it is and how to open it"
description: "A .jar file is a Java Archive. A zip of compiled Java classes — a library, or a runnable program. How to open one on Windows, macOS and Linux, and what to convert it to."
url: https://atoneplace.net/file/jar/
site: "At One Place"
---

# .jar files

**.jar file: Java Archive**

A zip of compiled Java classes — a library, or a runnable program.

## What opens a .jar file

- **Windows:** Java Runtime Environment (java -jar), 7-Zip (to inspect contents)
- **macOS:** Java Runtime Environment (java -jar), Archive Utility (built in, to inspect)
- **Linux:** Java Runtime Environment (java -jar), Archive Manager (to inspect)

## What a .jar file is

A JAR is a ZIP archive of Java bytecode plus a manifest, which may mark it as executable. Running one needs a Java runtime installed; with Java present, double-clicking usually works on Windows and macOS, and java -jar file.jar always does. Most JARs are libraries meant to be used by other code rather than launched, and Minecraft mods are the usual reason a non-developer has one.

## Converting it

A .jar file is commonly converted to .zip, .exe or .war. It is a binary format, so a text editor will show unreadable characters rather than its contents.

## Details

- **Extension:** .jar
- **Full name:** Java Archive
- **Category:** Programs and installers
- **MIME type:** application/java-archive
- **Created by:** Sun Microsystems / Oracle
- **Format:** Binary

## Common questions

### How do I open a .jar file?

On Windows use Java Runtime Environment (java -jar); on macOS use Java Runtime Environment (java -jar); on Linux use Java Runtime Environment (java -jar). A zip of compiled Java classes — a library, or a runnable program.

### What is a .jar file?

Java Archive. A JAR is a ZIP archive of Java bytecode plus a manifest, which may mark it as executable. Running one needs a Java runtime installed; with Java present, double-clicking usually works on Windows and macOS, and java -jar file.jar always does.

### Can I convert a .jar file?

Yes. It is usually converted to .zip, .exe or .war, either by exporting from one of the programs listed above or with a format converter.

## Related pages

- [.exe — Windows Executable](https://atoneplace.net/file/exe/)
- [.apk — Android Application Package](https://atoneplace.net/file/apk/)
- [.msi — Windows Installer Package](https://atoneplace.net/file/msi/)
- [.dll — Dynamic Link Library](https://atoneplace.net/file/dll/)
- [.sh — Shell Script](https://atoneplace.net/file/sh/)
- [.deb — Debian Software Package](https://atoneplace.net/file/deb/)
- [.bat — Windows Batch File](https://atoneplace.net/file/bat/)
- [.pkg — macOS Installer Package](https://atoneplace.net/file/pkg/)
- [.ps1 — PowerShell Script](https://atoneplace.net/file/ps1/)
- [.ipa — iOS Application Archive](https://atoneplace.net/file/ipa/)
- [.rpm — RPM Package](https://atoneplace.net/file/rpm/)
- [.appimage — AppImage Portable Application](https://atoneplace.net/file/appimage/)

## Sources

- Media Types Registry — IANA (https://www.iana.org/assignments/media-types/)
- Official vendor product documentation — At One Place (/about/)