Thinking about upgrading to JDK 25?
Azul’s Performance Engineering Lab tested the code speed of Azul Prime’s Zing distribution and other OpenJDK distributions in the market, using Java 11.0.30 as a baseline. Azul’s benchmarks measure overall code speed, and are not limited to only garbage collection (GC) pauses or ahead-of-time optimizations. The latest benchmarks tested Java 25 (JDK 25), the most recent LTS version, released in September 2025. The results are available in the High-Performance Java Platform Benchmark Report for 2026.
The report makes clear that, if you’re considering upgrading to JDK 25 and are concerned about performance, your best option would be a high-performance Java platform such as Azul Prime, which includes Azul Zing, an award-winning enhanced build of OpenJDK for superior application performance, responsiveness, and efficiency.
Key findings of the report
The key findings that relate to Java 25 are:
- In April 2026, OpenJDK 25 (25.0.1) was 16.4% faster than the baseline of OpenJDK 11.0.30 – delivering a significant performance boost for customers upgrading from OpenJDK 8 or 11. For customers on Java 17 or 21, the performance gains are more moderate.
- For customers looking to maximize performance, Azul Prime’s Zing JDK 25 (26.02) offers a 38.8% boost over the same OpenJDK 11 baseline and a 21.8% performance boost over OpenJDK 25.0.1
- OpenJDK 25 contains 18 JEPs, of which three provide the majority of its performance gains. These include ahead-of-time (AOT) optimizations and compact object headers.
Source: Java LTS benchmark study by the Azul Performance Engineering Lab
In the chart above, the first thing that jumps out is that every version of Azul Prime is faster than the fastest OpenJDK version, OpenJDK 25. Azul Prime’s JDK versions improve in performance over time, while OpenJDK versions remain static. When OpenJDK 17 and OpenJDK 21 were first released, users saw an initial boost in performance but, after that, the results remain essentially the same. For OpenJDK users, an upgrade to the next LTS version is required to achieve the next performance boost. Unfortunately, this wait can last as long as two years. It seems likely that OpenJDK 25 will follow a similar path.
In contrast, organizations using Azul Prime, even previous versions 17 and 21, can choose the optimal time to upgrade without sacrificing performance. Whenever they elect to upgrade to Java 25, they’ll benefit from continued performance boosts and Azul’s engineering investments in the coming months and years.
Plan now for JDK 29 LTS
Organizations using Oracle JDK 21 will need to move to a Java SE OTN license or upgrade to JDK 25 to receive updates after September 2026.
The next LTS Java release, JDK 29, is planned for release in September 2027, which will begin the one-year countdown to the end of permissive licensing for JDK 25.
What makes Azul Prime’s performance better?
Azul Prime includes Azul Zing, an award-winning enhanced build of OpenJDK. With Zing, what you run in production today will run at least 20% faster, without the need to change or recompile your code. In addition, we continue to work with our customers and the Java community to benchmark and improve Zing’s performance over time.
Azul Prime improves performance by:
- Optimizing resource utilization
- Removing GC pauses and glitches
- Reducing warm-up time
- Freeing up engineer time for tasks beyond performance tuning
Azul Prime, Azul’s high-performance Java platform, includes Azul Zing Builds of OpenJDK, which is enhanced for superior performance, consistency, and efficiency. Prime is also TCK-verified with Oracle’s Technology Compatibility Kit (TCK), a test suite that verifies that the Java implementation is compatible with the Java SE specifications. With Prime, organizations can maximize efficiency and minimize costs by delivering faster code, faster warmup times, and pauseless garbage collection. This means they use fewer resources to achieve the same or even greater performance. This efficiency enables organizations to save on infrastructure costs, especially expensive cloud instances.
Learn more in The High-Performance Java Platform Benchmark Report, and get started today with a free, expert-led Azul Prime trial, to see the benefits for your workloads.
