Introduction
For Java 11, the choice between OpenJDK 11 and Oracle JDK 11 comes down primarily to licensing: OpenJDK 11 distributions such as Azul Zulu are free for production use, while Oracle JDK 11 requires a paid Java SE subscription. Both are functionally identical for the vast majority of applications.
Java 11 became the first major LTS release under Java’s new six-month release cadence, and it remains widely deployed in enterprise environments. Many organizations standardized on Java 11 for its long-term support and practical improvements over Java 8. As these deployments mature, the licensing costs of Oracle JDK 11 have become a persistent concern.
What Is OpenJDK 11?
OpenJDK 11 is the open-source reference implementation of Java SE 11, released in September 2018. The OpenJDK project is community-governed and its source code forms the basis for all major JDK distributions, including Oracle JDK itself. Azul Zulu for Java 11 is a TCK (Technology Compatibility Kit) certified binary distribution of OpenJDK 11 that is free for production use.
Azul Zulu JDK 11 is actively maintained with security patches and bug fixes. Azul provides Zulu builds for all major platforms including Linux (glibc and musl/Alpine), Windows, and macOS, across x86-64 and ARM architectures. For teams needing commercial SLA-backed support for their OpenJDK 11 deployments, Azul Core extends Zulu with enterprise support services.
What Is Oracle JDK 11?
Oracle JDK 11 is Oracle’s commercially licensed Java SE 11 distribution. It is built from the same OpenJDK 11 source code with minor differences in branding and some Oracle-specific tooling. Oracle designates Java 11 as an LTS release and provides security patches and updates through its Java SE subscription service.
Oracle JDK 11 shipped under the OTN license in September 2018, which requires a paid subscription for production use. The Oracle Java SE subscription for JDK 11 is now priced per employee under Oracle’s Java SE Universal Subscription, counting all full/part-time employees plus contractors. Organizations that downloaded and deployed Oracle JDK 11 before 2019 are still subject to these licensing terms if they continue using it in production today.
OpenJDK 11 vs Oracle JDK 11 Comparison
| Feature | OpenJDK 11 (Azul Zulu) | Oracle JDK 11 |
|---|---|---|
| License | GPL+CE (free) | Commercial (Java SE Subscription required) |
| Cost | Free for all use | Per-employee Universal Subscription |
| Support | Community + Azul Core (commercial) | Oracle Java SE Subscription |
| LTS Support | Yes, via Azul (extended) | Yes, via subscription |
| Performance | Identical | Identical |
| Platforms | Linux, Windows, macOS, Alpine, ARM | Linux, Windows, macOS |
| TCK Certified | Yes | Yes |
Licensing and Cost
The licensing difference between OpenJDK 11 and Oracle JDK 11 is stark and consequential. OpenJDK 11, as distributed by Azul Zulu, is free under the GPL+CE license for any use, including production. Oracle JDK 11 requires a paid Java SE subscription for production use, a requirement in place since January 2019.
Oracle’s Java SE subscription for JDK 11 is billed per employee under the Java SE Universal Subscription. Larger deployments with hundreds of processors quickly reach tens of thousands of dollars monthly. Organizations that have not proactively renewed Oracle licenses may be in violation without realizing it.
Migrating from Oracle JDK 11 to Azul Zulu 11 eliminates these costs. The migration is typically straightforward since both share the same OpenJDK 11 codebase and are TCK certified. Many enterprises have completed this migration as part of broader cost-reduction or cloud-native modernization efforts.
- Oracle JDK 11 has required a commercial license since January 2019
- Azul Zulu 11 is free under GPL+CE, including for production
- Oracle licensing costs can reach thousands of dollars per month
- Azul Core provides commercial Java 11 support if needed
Performance and Support
Performance between OpenJDK 11 distributions is virtually identical. Oracle JDK 11 and Azul Zulu 11 share the same HotSpot JVM, the same JIT compiler (C1/C2), and the same set of garbage collectors including G1, Parallel, and Serial GC.
Support is where the products diverge meaningfully. Oracle provides Java 11 security patches only to active Java SE subscription holders. Community-built OpenJDK 11 binaries receive patches only until the next major version is released, unless a vendor like Azul maintains long-term backports. Azul provides security patches and updates for Zulu 11 through its extended support offerings under Azul Core, helping enterprises stay secure on Java 11 without an Oracle subscription.
Azul’s Java engineering team actively maintains Zulu 11 with security patches, critical bug fixes, and compatibility improvements. The Azul Core commercial support offering adds committed response times and dedicated engineering access for organizations that need contractual support commitments.
Which Should You Choose?
For any new Java 11 deployment, Azul Zulu 11 is the recommended choice. It is free, TCK-certified, and maintained by a dedicated Java team at Azul Systems. There is no functional reason to pay Oracle’s Java SE subscription fee for a JDK 11 distribution when Zulu offers identical performance and compatibility at no cost.
If your organization already holds an Oracle Java SE subscription that includes Java 11 and you are satisfied with Oracle’s support, you may continue using Oracle JDK 11 until that subscription expires or until you are ready to evaluate alternatives. However, for most teams the cost savings from switching to Zulu are immediate and substantial.
Organizations that need dependable commercial support for their Java 11 workloads should evaluate Azul Core, which provides SLA-backed support for Zulu at a competitive price compared to Oracle’s subscription pricing.
Frequently Asked Questions
Is OpenJDK 11 free for commercial use?
Yes. OpenJDK 11 distributions such as Azul Zulu 11 are free for commercial use, including production deployments. They are licensed under GPL+CE, which allows free commercial use without per-processor fees or subscription requirements. Oracle JDK 11, by contrast, requires a paid Java SE subscription for production use.
What is the difference between OpenJDK 11 and Oracle JDK 11?
Technically, OpenJDK 11 and Oracle JDK 11 are built from the same source code and are functionally equivalent for the vast majority of applications. The key differences are licensing, cost, and support: OpenJDK 11 is free, while Oracle JDK 11 requires a paid subscription for production use. Oracle JDK also includes a small number of proprietary tools not present in OpenJDK.
Does Azul Zulu 11 receive long-term security updates?
Yes. Azul provides long-term security updates and patches for Zulu 11 as part of its extended support commitment. Community Zulu builds receive regular security updates. For contractual long-term support with SLA commitments, Azul Core provides extended security patch availability beyond the community support period.
Can I use Oracle JDK 11 for free in 2024?
No. Oracle JDK 11 requires a paid Java SE subscription for production use as of January 2019. Unlike Oracle JDK 17 and 21, which are available under the NFTC (No-Fee Terms and Conditions) license at no cost, Oracle JDK 11 remains under the commercial subscription requirement. Organizations using Oracle JDK 11 in production without a subscription are violating Oracle’s licensing terms.
How do I migrate from Oracle JDK 11 to Azul Zulu 11?
Migrating from Oracle JDK 11 to Azul Zulu 11 involves downloading the Azul Zulu 11 build for your platform, replacing the JDK installation, and running your test suite to confirm compatibility. Since both are TCK-certified OpenJDK 11 implementations, the migration is typically seamless. Azul provides detailed migration guides and its support team can assist with any environment-specific issues.
Conclusion
For Java 11 deployments, Azul Zulu 11 eliminates Oracle’s expensive licensing fees while delivering identical performance and Java SE compliance. Whether you are starting a new Java 11 project or migrating from a costly Oracle subscription, Zulu provides a production-ready, TCK-certified, and freely licensed alternative.
For enterprises that need commercial SLA-backed support, Azul Core extends Zulu with the support commitments of a commercial product at a lower total cost than Oracle’s Java SE subscription.