Azul Intelligence Cloud The Powerful Analytics Solution That Boosts DevOps Efficiency with Insights from Production Java Runtime Data from Any JVM  

ZIUpdater Time Zone Tool

ZIUpdater is an open source tool developed by Azul that provides the ability to update the IANA time zone definitions for any installed Java instance.

ZIUpdater provides a functional subset of the equivalent Oracle tool TZUpdater.

  • The current version of ZIUpdater updates the time zone information obtained from any downloaded copy of the IANA time zone database.
  • ZIUpdater performs a compilation step, transforming the IANA database into a JDK-compatible file set, then applies it to the file tree of the invoked JDK/JRE.
  • You may use ZIUpdater on any platform (Windows, Linux, macOS, etc.) where you have installed Java.
  • By design, it works with Azul Zulu Builds of OpenJDK and Azul Zing Builds of OpenJDK, but ZIUpdater has also been successfully tested against OpenJDK and Oracle JDK.

To be precise, ZIUpdater works as a JAR file utility that operates against the Java installation of the JRE that invokes it. It compiles tzdata source information into files in binary format and puts these files into the Java installation directory.

For Java 8 and later, the source data is compiled into a single file placed at:
For Java 7 and earlier, the source data is compiled into multiple files placed at:

ZIUpdater can be used with the any version of time zone database available from IANA. See Using the Time Zone Updater Tool for details.


How to install


Unzip the download package, and run the JAR file against the Java installed set at your JAVA_HOME location.

$JAVA_HOME/bin/java -jar ziupdater.jar -l file://[path]/tzdata.tar.gz

For more information on how to run ZIUpdater, current version details, and other notes, please refer to the enclosed README file and Using the Time Zone Updater Tool.

As a reminder, please note that every Azul Platform Core and Azul Platform Prime release ships with the latest IANA time zone data files available at the time of release. Therefore updating your JDK/JRE and using ZIUpdater remain complementary actions; both are suitable tactics to ensure you are using the latest time zone definitions.

Please send questions/problems/source snapshot requests to [email protected]