Ubuntu 26.04 LTS ‘Resolute Raccoon’ will use OpenJDK 25 as its default Java version.
An expected change as OpenJDK 25 is a long-term support release, as Ubuntu 26.04 is, the bump brings various feature and performance improvements to developers over OpenJDK 21, the default version used in Ubuntu 24.04 LTS through 25.10.
On Ubuntu, Java isn’t installed out of the box, but when you install default-jdk or default-jre (directly or indirectly as a dependency needed by other software) those meta-packages point to whichever OpenJDK version Canonical has blessed as current.
In Ubuntu 26.04 LTS, that will be OpenJDK 25.
Version 25 of OpenJDK, the open-source reference implementation of Java SE platform, improves memory efficiency, garbage collection and ahead-of-time profiling for faster startup. A few long-gestating language features reach stable or near-stable status.
Given the important of Java in Ubuntu, Ubuntu’s engineers have been testing OpenJDK 25 out. A handful of build failures across dependent packages are in the process of being resolved, but the new packages are now being uploaded to the proposed repo.
All being well, OpenJDK 25 will be available to all users of Ubuntu 26.04 LTS when it’s released on April 23, 2026. Those who want (or need) to stick on OpenJDK 21 needn’t fret; older versions remain available to install from the repos.