Machine Learning Group at the University of Waikato

Downloading and installing Weka

There are two versions of Weka: Weka 3.8 is the latest stable version, and Weka 3.9 is the development version. For the bleeding edge, it is also possible to download nightly snapshots.

Stable versions receive only bug fixes, while the development version receives new features. Weka 3.8 and 3.9 feature a package management system that makes it easy for the Weka community to add new functionality to Weka. The package management system requires an internet connection in order to download and install packages.


Note (1) for users upgrading from Weka 3.7 to Weka 3.8 or later: if the Weka 3.8 package manager does not start up, please delete the file installedPackageCache.ser in the packages folder that resides in the wekafiles folder in your user home.

Note (2) for users upgrading from Weka 3.7 to Weka 3.8 or later: serialized models created in 3.7 are not compatible with 3.8. We have a model migrator tool that can migrate some models to be compatible with 3.8.0. One exception is RandomForest, which can be migrated up to 3.7.13 but no further. Usage is as follows:

java -cp <path to modelMigrator.jar>:<path to weka.jar> weka.core.ModelMigrator -i <path to old serialized weka model> -o <upgraded model file name>


  • Snapshots

    Every night a snapshot of the Subversion repository is taken, compiled and put together in ZIP files. For those who want to have the latest bugfixes, they can download these snapshots here.

  • Stable version

    Weka 3.8 is the latest stable version of Weka. This branch of Weka receives bug fixes only, although new features may become available in packages. There are different options for downloading and installing it on your system:

    • Windows

      Click here to download a self-extracting executable for 64-bit Windows that includes Oracle's 64-bit Java VM 1.8
      (weka-3-8-0jre-x64.exe; 105.5 MB)

      Click here to download a self-extracting executable for 64-bit Windows without a Java VM
      (weka-3-8-0-x64.exe; 50.2 MB)

      Click here to download a self-extracting executable for 32-bit Windows that includes Oracle's 32-bit Java VM 1.8
      (weka-3-8-0jre.exe; 100.8 MB)

      Click here to download a self-extracting executable for 32-bit Windows without a Java VM
      (weka-3-8-0.exe; 50.2 MB)

      These executables will install Weka in your Program Menu. Download the version without the Java VM if you already have Java 1.7 (or later) on your system.

    • Mac OS X

      Click here to download a disk image for OS X that contains a Mac application including Oracle's Java 1.8 JVM
      (weka-3-8-0-oracle-jvm.dmg; 125.8 MB)

    • Other platforms (Linux, etc.)

      Click here to download a zip archive containing Weka
      (weka-3-8-0.zip; 50.6 MB)

      First unzip the zip file. This will create a new directory called weka-3-8-0. To run Weka, change into that directory and type

      java -jar weka.jar

      Note that Java needs to be installed on your system for this to work. Also note, that using -jar will override your current CLASSPATH variable and only use the weka.jar.

  • Developer version

    This is the trunk of Weka and continues from the stable-3-8 code line. It receives both bug fixes and new features.

    • Windows x86

      Click here to download a self-extracting executable that includes Java VM 1.8
      (weka-3-9-0jre.exe; 100.7 MB)

      Click here to download a self-extracting executable without the Java VM
      (weka-3-9-0.exe; 50.1 MB)

      These executables will install Weka in your Program Menu. Download the second version if you already have Java 1.7 (or later) on your system.

    • Windows x64

      Click here to download a self-extracting executable that includes 64 bit Java VM 1.8
      (weka-3-9-0jre-x64.exe; 105.4 MB)

      Click here to download a self-extracting executable without the Java VM
      (weka-3-9-0-x64.exe; 50.1 MB)

      These executables will install Weka in your Program Menu. Download the second version if you already have Java 1.7 (or later) on your system.

    • Mac OS X

      Click here to download a disk image for OS X that contains a Mac application including Oracle's Java 1.8 JVM
      (weka-3-9-0-oracle-jvm.dmg; 125.7 MB)

    • Other platforms (Linux, etc.)

      Click here to download a zip archive containing Weka
      (weka-3-9-0.zip; 50.4 MB)

      First unzip the zip file. This will create a new directory called weka-3-9-0. To run Weka, change into that directory and type

      java -jar weka.jar

      Note that Java needs to be installed on your system for this to work. Also note, that using -jar will override your current CLASSPATH variable and only use the weka.jar.

  • Old versions

    All old versions of Weka are available from the Sourceforge website.