Amazon Corretto 25, a Long Term Support (LTS) version, is now generally available. Amazon Corretto is a no-cost, multi-platform, production-ready distribution of OpenJDK . You can download Corretto 25 for Linux, Windows, and macOS from our downloads page .
Amazon Corretto 25 new features include:
- Two features that were initially released as experimental in JDK 24 are now LTS production-ready in JDK 25:
Compact Object Headers: designed to lower heap memory usage by shrinking object headers from 96-128 bits down to 64 bits.
Generational Shenandoah GC: engineered to provide sustainable throughput and lower p99 pause times or similar pause times with a smaller heap and reduced CPU usage. - Ahead-of-Time (AOT) Caching: designed to improve cold-start and warm-up time by reusing pre-parsed pre-linked classes and compilation profiles between training and production runs.
- Language improvements: primitive types in patterns, flexible constructors, module‑wide imports, compact source files, scoped values for thread-local variables, stable values for immutable data, all designed to cut boilerplate, keep everyday code shorter and safer.
- Observability: JDK Flight Recorder gains CPU‑time sampling, cooperative sampling and method‑trace events for low‑overhead production profiling.
- Structured Concurrency: designed to provide coordinated task management, allowing related tasks fail or finish together.
- Vector API: developed to provide computations that compile to optimal vector instructions on supported CPUs.
- Virtual Thread pinning improvements: reduces thread pinning in synchronized blocks for better scalability.
A detailed description of these features can be found on the OpenJDK 25 Project page . Amazon Corretto 25 is distributed by Amazon under an open source license and will be supported through October 2032.