Free online JAR to ZIP converter

A program, archive utility, or device may accept .zip while rejecting the equivalent .jar filename. Because JAR files use the ZIP archive structure, renaming the extension usually supplies the required format without changing the archive data.

What the JAR format is

JAR, or Java Archive, is a ZIP-based container for Java class files, libraries, resources, metadata, and sometimes an executable application. Java developers create JAR files with the JDK's jar tool, build systems such as Maven and Gradle, and IDEs such as IntelliJ IDEA and Eclipse.

An executable JAR can contain META-INF/MANIFEST.MF with a Main-Class entry that identifies the class Java should run. Libraries may also contain dependency metadata, service definitions, license files, and digital-signature data.

What the ZIP format is

ZIP is a general-purpose archive format supported by Windows, macOS, Linux, file managers, backup software, and many devices. It stores one or more files in a container and can compress individual entries using ZIP-supported methods.

JAR is not a different compression technology that must be decoded and converted to ZIP: its archive structure is ZIP-compatible. A .zip filename is useful when receiving software checks the extension or when the contents need to be opened with a standard archive utility.

How to convert a JAR file to ZIP

Rename the extension

1. Make a backup copy of the original JAR.
2. Rename example.jar to example.zip. In Windows File Explorer, enable View → Show → File name extensions first; otherwise, the result could be example.zip.jar.
3. Open the renamed file in the target program or extract it with a ZIP utility.

On macOS or Linux, run mv example.jar example.zip. In Windows PowerShell, run Rename-Item example.jar example.zip. Renaming preserves the archive byte-for-byte, including its compression, paths, timestamps, comments, and signatures.

Repackage the archive

Repackage the contents only when the receiving software rejects a renamed JAR, or when files must be edited before the ZIP is created. Extracting and creating a new archive changes the archive structure and may invalidate JAR-specific properties.

1. Create a temporary directory and extract the JAR with the JDK: mkdir jar_contents, then cd jar_contents and jar -xf ../example.jar.
2. Create the ZIP from the extracted contents, rather than from the directory containing them: zip -r ../example.zip .. The zip command is commonly available on macOS and Linux; install or use a ZIP utility if it is absent.
3. Open the result and verify the expected top-level entries, including META-INF when it was present in the source.

The jar extraction command is supplied with a JDK. On Windows, 7-Zip can handle both operations: choose 7-Zip → Extract to for the JAR, select the extracted files, then choose 7-Zip → Add to archive and set the archive format to zip.

Use the built-in converter

You can convert the file for free on 101convert.com without installing software. For confidential, proprietary, or signed archives, rename or repackage the file locally instead of uploading it to an online service.

Compatibility and quality limits

Renaming is the safest option when only ZIP recognition is needed because it does not recompress or modify the archive. Repackaging can alter compression ratio, entry order, timestamps, file permissions, comments, directory entries, and other archive metadata; it is not guaranteed to produce a smaller file.

Renaming preserves an executable JAR's ability to run when Java or the receiving launcher recognizes the archive despite its new extension, but software that specifically requires a .jar filename may reject the renamed file. Keep the original extension for Java execution and dependency resolution unless the consuming software explicitly accepts ZIP.

JAR signature files such as META-INF/*.SF, META-INF/*.RSA, and META-INF/*.DSA authenticate the original archive entries. Renaming preserves those signatures; extracting and rebuilding the archive normally invalidates them. Preserve the original JAR whenever signature validation, dependency verification, or exact byte-level reproducibility matters.