Once you decide to move off Oracle Java SE, the next question is which free OpenJDK build to standardize on. The four leading OpenJDK distributions — Eclipse Temurin, Amazon Corretto, Azul Zulu, and BellSoft Liberica — are all free for production and all remove Oracle's per-employee subscription liability. This is the buyer-side comparison Oracle won't give you.
Short answer: Eclipse Temurin, Amazon Corretto, Azul Zulu, and BellSoft Liberica are the four leading OpenJDK distributions — all free for production commercial use, all TCK-verified, and all built from the same OpenJDK source. None requires an Oracle Java SE subscription. The right choice depends on your cloud platform, LTS support window, and whether you need vendor-backed commercial support.
An OpenJDK distribution is a free, buildable, ready-to-run package of the open-source Java reference implementation, produced by a vendor and certified against the Java SE specification. OpenJDK is the upstream source project that Oracle JDK itself is compiled from; a distribution is simply a particular vendor's compiled, tested, and supported build of that source.
The critical point for buyers is that all reputable distributions share the same codebase and pass the same TCK (Technology Compatibility Kit), so they are functionally interchangeable for the vast majority of workloads. What differs is the wrapper around the binary: how long each version is supported for free, how quarterly security updates are delivered, which platforms and architectures are built, and whether the vendor sells a commercial support contract on top. Those wrapper differences — not the Java itself — are what this comparison is about. For the underlying licensing distinction, see our OpenJDK vs Oracle JDK licensing breakdown, and the broader picture in our Oracle Java Licensing Guide.
All four are free for production, GPLv2-with-Classpath-Exception licensed, and TCK-verified. The table below ranks them on the dimensions that actually decide an enterprise migration: vendor, LTS posture, platform breadth, commercial support, and best-fit scenario.
| Distribution | Vendor | License | Free production use | Commercial support | Best fit |
|---|---|---|---|---|---|
| Eclipse Temurin | Eclipse Adoptium (community) | GPLv2 + CPE | Yes — no fee | Via third parties (IBM, Azul, etc.) | Vendor-neutral standard across mixed estates |
| Amazon Corretto | Amazon (AWS) | GPLv2 + CPE | Yes — no fee | Included for AWS customers | AWS-centric and hybrid cloud estates |
| Azul Zulu | Azul Systems | GPLv2 + CPE | Yes — no fee (Community) | Paid (Azul Platform Core / Prime) | Widest version/platform matrix; legacy Java 6/7 |
| BellSoft Liberica | BellSoft | GPLv2 + CPE | Yes — no fee | Paid (BellSoft) | Full JDK with JavaFX; official Spring runtime; containers |
| Reference point: Oracle JDK requires a paid Java SE Universal Subscription ($5.25–$15.00 per employee per year) for production commercial use. Every distribution above removes that obligation entirely. | |||||
The headline: there is no wrong free choice among these four for standard server, desktop, and container workloads. The decision is about operational fit and support strategy, not capability. Where you do need to be careful is mixing distributions without governance — that creates patch-cadence drift and weakens your audit story.
We benchmark distribution fit against your estate and build the migration plan buyer-side — then use it as leverage if you still need a bridge subscription. Not affiliated with Oracle Corporation.
Eclipse Temurin is the vendor-neutral OpenJDK distribution maintained by the Eclipse Adoptium project, and it is the most widely downloaded free Java runtime in the enterprise. Because it is governed by a foundation rather than a single commercial vendor, Temurin is the safest default when you want a standard that no one supplier controls.
Temurin provides TCK-verified builds for Java 8, 11, 17, and 21 across Windows, Linux, and macOS on x64 and AArch64. Quarterly security updates track the upstream OpenJDK release cadence. The trade-off is that Adoptium does not itself sell a support contract — if you require a vendor SLA, you obtain commercial support for Temurin through third parties such as IBM or Azul. For most organizations migrating desktops, containers, and standard server workloads off Oracle Java, Temurin is the cleanest answer and the one we most often recommend as the estate-wide standard. It pairs naturally with the migration sequencing in our Java estate inventory guide.
Amazon Corretto is Amazon's free, production-ready OpenJDK distribution, with long-term support and quarterly security updates provided at no cost — and bundled support for AWS customers running it on AWS infrastructure. For AWS-centric estates, Corretto is the path of least resistance.
Corretto ships TCK-verified builds for Java 8, 11, 17, 21, and current releases, and Amazon backports security and stability fixes from its own production use of Java at scale. It runs anywhere — not just on AWS — but its strongest argument is for organizations whose footprint is already concentrated in Amazon's cloud, where it integrates cleanly with managed services and container base images. If your AWS spend is significant, Corretto removes Oracle Java cost without adding a new vendor relationship. Our Oracle Java to Amazon Corretto migration guide covers the move step by step.
Azul Zulu is Azul Systems' OpenJDK distribution, offered free as Zulu Community and with paid support through Azul Platform Core. Zulu has the broadest version and platform matrix of the four — including builds for legacy Java 6 and 7 and a wide range of operating systems and architectures.
That breadth makes Zulu the strongest fit for enterprises with long-lived legacy estates that need certified builds of older Java versions Oracle has long since moved behind extended-support paywalls. Azul also offers a commercial tier with vendor SLAs and, separately, Azul Platform Prime — a paid, performance-optimized runtime that is a different product from the free Zulu builds. For migration purposes, free Zulu Community is the relevant comparison, and it removes Oracle Java SE liability identically to the others. Where an enterprise wants a single commercial vendor to stand behind both modern and legacy Java, Azul is the natural conversation.
Watch the tier boundary. Azul and BellSoft both publish a free community runtime and a paid commercial tier. The free tiers carry no license fee for production. Make sure procurement understands you are adopting the free distribution — not silently signing into a paid support contract you didn't budget for.
BellSoft Liberica is a free OpenJDK distribution notable for its Full JDK builds that bundle JavaFX, its small-footprint container images (Liberica Lite and Alpaquita Linux), and its status as the recommended runtime for the Spring framework. For Spring-heavy and containerized estates, Liberica is purpose-built.
Liberica provides TCK-verified builds across Java 8, 11, 17, 21, and current versions, on the widest set of architectures including ARM for embedded and edge use. The Full builds matter for organizations that still depend on JavaFX or Java Web Start-style desktop applications, which were stripped out of Oracle JDK after Java 8 — Liberica Full re-bundles them, free. BellSoft sells optional paid support for enterprises that need an SLA. As with Zulu, the free distribution is what removes Oracle Java cost; the paid tier is purely optional support.
Standardize on one distribution across the estate wherever possible — the discipline of a single build matters more than which of the four you pick. As a buyer-side rule of thumb: Temurin if you want neutrality, Corretto if you live on AWS, Zulu if you need legacy versions or one commercial vendor for everything, and Liberica if you are Spring-heavy or need JavaFX.
The reason standardization matters is compliance defensibility. A mixed estate of four distributions with different patch cadences is harder to inventory, harder to keep current, and harder to prove clean if Oracle ever asserts that residual Oracle JDK survived your migration. One distribution, one patch process, one inventory. Whatever you choose, the financial outcome against Oracle is the same: you eliminate a Java SE subscription that, in our engagement data, runs 5–10× the cost of the old Named User Plus model for the equivalent deployment (Oracle Licensing Experts, 2026).
The migration itself is rarely the hard part — the governance is. Decommissioning Oracle JDK cleanly, proving no Oracle-branded Java remains, and timing the move ahead of any audit window is where most value is won or lost. That is the work our buyer-side Java Licensing service runs, and our Oracle Audit Defense team holds the line if Oracle challenges the result. See the telecom Java audit defense case study, where a $4.2M Java claim was reduced to $0 after a clean migration.
We map the four OpenJDK options to your real estate, sequence the migration, and keep you audit-defensible — entirely on the buyer's side of the table.
Yes. Eclipse Temurin, Amazon Corretto, Azul Zulu, and BellSoft Liberica are all distributed under the GPLv2 with Classpath Exception and are free for production commercial use with no per-employee or per-server license fee. Paid options exist only for optional commercial support, never for the runtime binary itself.
Eclipse Temurin is the most vendor-neutral default; Amazon Corretto suits AWS-heavy estates; Azul Zulu offers the widest version and platform coverage with commercial support; BellSoft Liberica is strongest for full JDK builds with JavaFX and small-footprint containers. All four remove Oracle Java SE subscription liability.
OpenJDK is the free, open-source reference implementation of Java that all major distributions and Oracle JDK are built from. Oracle JDK is Oracle's branded build, which requires a paid Java SE Universal Subscription for production commercial use. OpenJDK distributions deliver the same functionality without that license obligation.
Yes. Eclipse Temurin, Amazon Corretto, Azul Zulu, and BellSoft Liberica all publish TCK-verified builds, meaning each is certified compatible with the Java SE specification for its version. TCK verification is the technical reason migration off Oracle JDK is typically a drop-in replacement requiring no application code changes.
Free LTS windows vary by vendor. Amazon Corretto and Eclipse Temurin commit to multi-year support on LTS releases (8, 11, 17, 21). Azul Zulu Community provides long free support windows, and BellSoft Liberica offers extended free LTS. Azul and BellSoft additionally sell paid extended support beyond the free windows.
Technically yes, since all are TCK-verified, but it is not advisable. Mixing distributions creates divergent patch cadences and a harder inventory, which weakens your position if Oracle audits for residual Oracle JDK. Standardizing on one distribution gives you one patch process and a cleaner, more defensible compliance posture.
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Oracle Licensing Experts Team — Former Oracle licensing executives, LMS auditors, and contract managers, now working exclusively for enterprise buyers. Not affiliated with Oracle Corporation. About our team →
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