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How to Open JAR Files on Android

Browse a Java archive, read its manifest, inspect contained files and understand when a JAR can actually run on Android.

Quick answer

Use a JAR viewer to inspect the archive

A JAR is a ZIP-based archive used to package Java classes, resources and metadata. On Android, open it with a dedicated JAR viewer, select the file from device storage, and browse entries such as META-INF/MANIFEST.MF, .class files, text, images and bundled resources. Browsing a JAR is different from running its Java code.

Open a JAR file on Android

  1. Install Jar File Opener from its official app page or Google Play.
  2. Open the app and choose Open JAR File.
  3. Select the .jar file using Android's system file picker. If it arrived through email or a browser, check the Downloads folder.
  4. Browse folders inside the archive. Start with META-INF to find the manifest, then inspect classes and resources.
  5. Open supported entries or extract files you own to a separate folder. Keep the original archive unchanged when possible.

What is normally inside a JAR?

JAR files use the ZIP container format but add Java-specific conventions. A small application archive might look like this:

META-INF/ MANIFEST.MF com/example/ Main.class AppWindow.class config/ application.properties images/ icon.png

The archive may contain compiled Java bytecode, configuration files, images, service-provider files, signatures or source code. A library JAR may have no runnable entry point at all.

META-INF/MANIFEST.MF

Manifest metadata

May describe the manifest version, main class, class path, module name and other package attributes.

*.class

Compiled Java classes

Java bytecode compiled for a particular class-file version. A viewer can inspect or decompile supported files without executing them.

META-INF/services/

Service providers

Configuration files used by Java's service-provider loading mechanism.

*.SF / *.RSA / *.EC

Signing files

Signature-related entries may be present in signed archives. Their presence alone is not verification of trust.

Opening a JAR is not the same as running it

Opening means reading the archive structure and viewing contained files. This is similar to opening a ZIP file and does not start Java bytecode. Running a JAR requires a compatible Java runtime, an entry point and all required dependencies.

A directly runnable JAR normally declares a Main-Class in its manifest. Desktop Java can launch one with java -jar app.jar. Android does not provide a standard desktop Java launcher for arbitrary JAR applications, so compatibility depends on the runtime, Java version and APIs used. For compatible programs, see Jre4Android.

View a JAR on a computer

If the JDK is installed, the official jar command can list or extract archive entries. Extraction recreates the stored folder structure and may overwrite matching files in the destination, so use a new folder.

jar tf app.jar
jar xf app.jar
jar xf app.jar META-INF/MANIFEST.MF

Why a JAR file may not open or run

  • Incomplete download: the archive ends early or its central directory is damaged. Download the file again from the original source.
  • Wrong extension: a file named .jar may not actually contain a ZIP/JAR structure. Use the File Inspector to check its signature.
  • No Main-Class: many JARs are libraries and are not intended to launch with java -jar.
  • Missing dependencies: required libraries may be absent or referenced by the manifest's Class-Path.
  • Unsupported Java version: the contained classes may target a newer Java release than the available runtime.
  • Desktop-specific APIs: Swing, AWT, native libraries or operating-system integrations may not work in an Android runtime.

Safety and copyright

A JAR can contain executable Java bytecode. Browsing its directory or reading text entries is static inspection, but running unknown code can still be risky. Only run software from a source you trust, and only extract, inspect or decompile files you own or have permission to analyze.

JAR file FAQ

Why does Android show my JAR as a ZIP file?

That is expected because JAR uses the ZIP container format. The .jar extension and Java-specific metadata distinguish its intended use.

Can I open a JAR without executing it?

Yes. A JAR viewer can list folders and display supported entries without invoking the Java runtime or running contained classes.

Can every JAR file run on Android?

No. A runnable entry point, compatible bytecode, required dependencies and supported APIs are all needed. Library JARs and desktop applications may not run.

Where is MANIFEST.MF stored?

The conventional path is META-INF/MANIFEST.MF at the archive root. Read the separate MANIFEST.MF guide for field explanations.

Is it safe to rename ZIP to JAR?

Renaming changes only the filename. It does not add compiled classes, a valid manifest or the structure required by a Java application.

Technical source

Archive structure and manifest terminology follow Oracle's JAR File Specification and official JAR tool tutorial. Last reviewed August 14, 2026.