Five enterprise grade OpenJDK distributions, all free in production, all functionally equivalent to Oracle JDK at the same Java version. The choice between them is operational, not technical. This is the buyer side comparison we run on every Oracle Java exit.
OpenJDK is the open source codebase that Oracle Java itself is built from, so moving to a free distribution is a procurement and security exercise, not a code rewrite.
OpenJDK is the open source reference implementation of Java Standard Edition, and Oracle Java is a commercial build of it. At the same version the two behave the same for the vast majority of workloads.
Sun Microsystems opened the code in 2007 and Oracle inherited it in 2010. Oracle remains the largest contributor, which is why the alternatives are not weaker forks. They are the same upstream, packaged by different vendors. The project lives at the OpenJDK project site, under GPL version 2 with the Classpath Exception, which permits free production use.
No. Free covers the binary and the regular security updates. Paid support adds an SLA, named engineers, and patches for older versions. Most estates run free in production and buy support only where the SLA is contractual.
Pick the distribution that matches your dominant cloud or operating system, and default to Eclipse Temurin when the estate is mixed. The choice is operational, not technical.
The five enterprise OpenJDK distributions in 2026
| Distribution | Vendor | LTS coverage | Free in production |
|---|---|---|---|
| Eclipse Temurin | Adoptium (Eclipse Foundation) | 8, 11, 17, 21 | Yes |
| Azul Zulu | Azul Systems | 7, 8, 11, 17, 21 plus extended LTS | Yes |
| Amazon Corretto | Amazon Web Services | 8, 11, 17, 21 | Yes |
| Microsoft Build of OpenJDK | Microsoft | 11, 17, 21 | Yes |
| Red Hat build of OpenJDK | Red Hat (IBM) | 8, 11, 17, 21 | Yes, with a RHEL subscription |
Eclipse Temurin from Adoptium is the vendor neutral default. Eclipse Foundation governance, broad version coverage, and the largest community make it the safest pick when no single cloud dominates the estate.
Cloud concentration usually decides it. Amazon Corretto fits AWS heavy estates, and Microsoft Build of OpenJDK fits Azure and Microsoft 365 heavy estates. Both ship free and align to the cloud provider support cadence.
The buyer side fit by operational profile
| If your estate is | Default distribution | Why |
|---|---|---|
| Mixed, multi cloud, multi OS | Eclipse Temurin | Vendor neutral, broadest coverage, largest community. |
| AWS heavy | Amazon Corretto | Managed by AWS, free with AWS workloads. |
| Azure or M365 heavy | Microsoft Build of OpenJDK | Managed by Microsoft, free for Azure and M365 customers. |
| Red Hat Enterprise Linux heavy | Red Hat build of OpenJDK | Bundled with the existing RHEL subscription. |
| Latency sensitive or regulated | Azul Zulu Prime | Strongest support tier and a low pause garbage collector. |
Most enterprises run free OpenJDK in production and buy support only for regulated, latency sensitive, or legacy workloads. The contract replaces the operational tier Oracle bundled into the subscription.
The major paid OpenJDK support routes in 2026
| Vendor | What you get | Pricing model | Best fit |
|---|---|---|---|
| Azul Platform Core and Prime | SLA support, extended LTS, low pause runtime | Per server or per core | Large, regulated, or latency sensitive estates |
| Adoptium partners | Support on Temurin without changing the binary | Varies by partner | Temurin users who want an SLA |
| BellSoft Liberica | Production support with bespoke patches | Per server or per core | Embedded and native image use cases |
| IBM Semeru | IBM standard support tier | Bundled with IBM platform subscriptions | IBM platform and OpenJ9 estates |
Far cheaper, and for a structural reason. The Oracle Java SE Universal Subscription bills per total employee, while OpenJDK support bills per deployment. In our engagement file the support contract usually lands at 3 to 12 percent of the Oracle figure at the same scale.
Budget twelve to eighteen months for a full enterprise estate. The calendar is driven by validation and third party software, not by the runtime swap, which is quick.
The standard reseller and account team pitch is that leaving Oracle Java is risky and that the Universal Subscription is the safe, simple option. We disagree. In roughly 30 of the 40 Oracle Java estates we benchmarked across 2024 and 2025, the runtime cutover was low risk, and the only real risk sat in third party software and in the contract calendar, not in the Java itself. The buyer side move is to run a six week pilot, inventory embedded Java early, and time the formal non renewal to the contract cycle. Framed that way the subscription is a commercial choice, not a technical necessity.
Source: Redress Compliance advisory engagement file, 2024 to 2025.
The hard part of leaving Oracle Java is never the Java. It is the software you forgot was carrying it.
Yes. At the same Java version OpenJDK and Oracle JDK are functionally equivalent for almost every enterprise application. Oracle JDK is built from the OpenJDK codebase with a small set of commercial additions most applications never touch, so code that runs on one runs on the other with no changes in nearly all cases.
Eclipse Temurin from the Adoptium project is the vendor neutral default for a mixed estate. Run Amazon Corretto on AWS heavy estates, Microsoft Build of OpenJDK on Azure heavy estates, and the Red Hat build of OpenJDK where it is already bundled with a Red Hat Enterprise Linux subscription.
Yes. All five major enterprise distributions are free for production under GPL version 2 with the Classpath Exception. Optional paid support contracts cost a small fraction of the Oracle Java SE Universal Subscription, usually 3 to 12 percent of the equivalent Oracle bill at the same scale.
Budget twelve to eighteen months for a full enterprise estate. The first three months are inventory and a pilot, months four to nine are the phased rollout, and the final stretch covers developer workstations, third party software, and the formal non renewal of the Oracle subscription.
Most enterprises run free OpenJDK in production and buy support only where it is needed. Regulated, latency sensitive, or legacy workloads justify a contract from Azul, BellSoft, IBM, or an Adoptium partner. The support is sized to deployment, not to total employees, which is the structural advantage over the Oracle metric.
Third party software that ships embedded Oracle JDK. Many enterprise products bundle Oracle Java inside installers or container images, so the buyer stays exposed until those binaries are migrated too. Inventory embedded Java early and ask each vendor for an OpenJDK compatible build.
Not if the exit is documented. The risk is the opposite, leaving the Oracle subscription in place while the estate quietly drifts onto free OpenJDK. Keep a dated binary inventory, complete the cutover, and issue formal non renewal so the audit posture is clean and defensible.
Yes. The Vendor Shield subscription covers Oracle Java in every tier, including distribution selection, paid support negotiation, the migration calendar, and the post exit audit posture.
The buyer side framework for the broader Oracle commercial decision. The ULA exit framework, the certification framework, the renewal framework, and the broader Oracle commercial posture across the next renewal cycle.
Used across more than five hundred enterprise software engagements. Independent. Buyer side.
Open the white paper in your browser. Corporate email only.
Open the Paper →We assumed the OpenJDK migration was going to be a code rewrite. It was not. The pilot took six weeks on a non critical application. The phased production rollout took eight months. The Oracle Java SE Subscription non renewed at the next cycle. The annual saving was nine point two million dollars.
