Amazon Corretto 25 is now generally available

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.