Oracle OpenJDK is free to use, but its licensing, support, and update policies are nuanced. Understanding the details ensures you can use Oracle OpenJDK effectively without incurring unexpected costs.
This article covers exactly what Oracle OpenJDK is, its licensing terms, how updates and security patches work, and whether it remains free indefinitely.
What is Oracle OpenJDK?
Oracle OpenJDK is Oracle’s open-source Java Development Kit (JDK) distribution. It’s based directly on the source code of the OpenJDK project, maintained by Oracle and the broader Java community. Unlike Oracle’s proprietary Java SE, Oracle OpenJDK is fully open-source and licensed under the GNU General Public License version 2 with Classpath Exception (GPLv2+CPE).
Oracle provides binaries of OpenJDK that developers and enterprises can freely download, distribute, and use without licensing fees. However, “free” primarily refers to cost and licensing, not necessarily ongoing updates, support, or long-term security patch availability.
Understanding Oracle OpenJDK Licensing (GPLv2+CPE)
Oracle OpenJDK is distributed under the GPLv2 license with Classpath Exception:
- GPLv2: The GNU General Public License requires derived works or modifications to be open-source under the same license. If you redistribute the OpenJDK, changes must remain open-source.
- Classpath Exception (CPE): This important exception permits applications developed on Oracle OpenJDK to be licensed under different licenses (including proprietary ones), even though the underlying JDK is GPL-2-licensed.
This licensing structure ensures that Oracle OpenJDK can be used freely, even in commercial environments, without requiring users to open-source their proprietary software.
How Oracle OpenJDK Compares to Oracle Java SE
Oracle provides two types of JDKs:
- Oracle Java SE: Oracle’s commercial, proprietary version of Java. It has paid subscription licensing for production use, particularly for updates and ongoing support.
- Oracle OpenJDK: Fully open-source, free to use, distribute, and modify. It typically offers no cost associated with use or distribution. However, official long-term support (LTS) availability directly from Oracle is limited compared to Java SE subscriptions.
To clarify:
- If you’re using Oracle Java SE, particularly the LTS versions like Java 17 or Java 21, you pay Oracle if you want ongoing security updates after the free support period ends.
- If you’re using Oracle OpenJDK, you pay nothing for using and redistributing the software, but Oracle provides limited official support.
Oracle OpenJDK Updates and Support Policy
Oracle’s Release and Update Schedule
Oracle releases new JDK versions every six months:
- Non-LTS Versions: These versions, like Java 18 or Java 19, receive updates for only six months. After that, users must move to a newer version to get continued updates.
- Long-Term Support (LTS) Versions: Released every two years (e.g., Java 17, Java 21), these are intended for longer-term stability. Oracle provides updates for these LTS versions for an extended period—but typically only for customers with paid Oracle Java SE subscriptions.
Read how Oracle Java 6 licensing works.
Oracle OpenJDK Updates Availability
Oracle initially provides binaries and updates for the OpenJDK version corresponding to each JDK release, but only for six months after the release date. This holds for both non-LTS and LTS versions:
- Public Updates for Oracle OpenJDK: They are freely available for six months per release, regardless of LTS status. For example, when Java 21 was released in September 2023, Oracle OpenJDK 21 binaries were freely available and updated publicly for only six months until March 2024.
- After this brief period, Oracle will stop publishing free public OpenJDK updates. At this point, Oracle’s builds become unavailable or unsupported without a paid subscription.
This means that Oracle’s OpenJDK binaries remain free indefinitely, but the official updates stop after six months. Users looking for ongoing updates and security patches beyond Oracle’s brief update period must find an alternative OpenJDK provider or pay Oracle for Java SE subscriptions.
How to Continue Using OpenJDK for Free (Long Term)
Since Oracle only updates OpenJDK binaries for six months, organizations seeking long-term, secure, and free OpenJDK use typically adopt builds from alternative providers. Several popular community-maintained distributions provide continuous, long-term security updates and are completely free.
Alternative Free OpenJDK Distributions
- Eclipse Temurin (Adoptium): A well-known OpenJDK distribution provided by the Eclipse Foundation. It’s widely adopted and offers free, long-term security patches, often for several years, matching Oracle’s LTS timelines.
- Amazon Corretto is Amazon’s own OpenJDK distribution, designed specifically to be free and supported for the long term. It is widely used in AWS and elsewhere, offering extended support and security updates completely free of charge.
- Azul Zulu Community Edition: Azul offers free community builds of OpenJDK with ongoing updates for multiple years. These builds match Oracle’s LTS release cycles, ensuring long-term stability and security.
- Red Hat OpenJDK: Typically included with Red Hat Enterprise Linux (RHEL), it receives long-term support and security updates at no extra cost beyond your OS subscription.
Example Scenario:
Imagine your company deployed Oracle OpenJDK 17 in 2022. Oracle stopped providing free public security updates after March 2022, six months after its release. Your Java version continued functioning, but vulnerabilities were discovered in subsequent months.
To stay secure without paying Oracle, you could switch your Java runtime to Adoptium’s Temurin or Amazon Corretto, which have provided ongoing, free security patches for Java 17 for years.
Limitations and Potential Costs of Oracle OpenJDK
While Oracle OpenJDK itself is free, certain indirect costs or limitations exist:
- Limited Oracle Direct Support: Oracle does not provide direct support or patching beyond six months. Companies seeking direct Oracle support must buy a paid Java SE subscription.
- Third-party support: Relying on community-supported builds means your support comes via forums, issue trackers, or paid third-party services rather than direct Oracle engineering.
- Maintenance burden: Ensuring compatibility and staying updated involves regularly migrating or updating your runtime if you choose free alternatives. Although most free distributions ensure excellent compatibility, this ongoing process might involve additional internal management or operational overhead.
Common FAQs about Oracle OpenJDK’s Free Use
Is Oracle OpenJDK free for commercial use?
Yes. Oracle OpenJDK is licensed under GPLv2+CPE, allowing completely free use in commercial environments. No licensing fees apply.
Can I redistribute Oracle OpenJDK?
Yes. The GPLv2 license permits redistribution freely, but modifications to the OpenJDK source must remain open-source.
Are Oracle’s updates for OpenJDK always free?
Free public updates are available only for the first six months after a release. Beyond this point, Oracle stops them. Users who want continuous free updates must switch to another OpenJDK provider like Adoptium or Corretto.
Can I use Oracle OpenJDK to avoid Oracle’s Java SE subscription?
Yes—but carefully. Oracle OpenJDK is free but doesn’t provide ongoing updates beyond six months. If you rely on Oracle’s direct security patches long-term, you’ll likely need to pay Oracle or use a third-party distribution for ongoing free updates.
Best Practices for Using Oracle OpenJDK Free of Charge
To effectively use Oracle OpenJDK without cost, consider these practices:
- Choose an LTS Version: Always pick Long-Term Support versions like Java 17 or Java 21. They ensure compatibility and updates from the community distributions for several years.
- Select a Community Distribution Early: After Oracle’s short free update period ends, migrate to a community-supported distribution like Adoptium or Corretto.
- Regular Security Patching: Establish internal processes for regular Java updates using your chosen community distribution, reducing vulnerabilities and maintaining compliance without unexpected costs.
Conclusion: Is Oracle OpenJDK Truly Free?
Oracle OpenJDK itself is completely free: free to use, distribute, and modify. However, official security updates directly from Oracle stop after six months. Users must buy Oracle Java SE subscriptions or switch to community-supported OpenJDK distributions that offer free, long-term security updates.
Organizations needing stable, secure, and free Java runtimes for long-term use should adopt alternative OpenJDK distributions like Adoptium (Temurin), Amazon Corretto, or Azul Zulu. Doing so allows ongoing, cost-free use of Java while avoiding licensing fees or the risks of running outdated software.
In short, Oracle OpenJDK is free, but the critical factor is ongoing access to updates. Understanding this ensures your Java usage remains both cost-effective and secure in the long term.
