Java (Temurin JDK)
Open sourceEclipse Temurin JDK · Eclipse Adoptium
- Category
- Development
- Version
- 21.0.12.101
- Manifest checked
- 2026-10-23
- Size
- ~171 MB
- Licence terms
- Open source (GPLv2 + Classpath) · free for personal and business use
- Supported OS
- Windows 11 · 10
- Install method
- Automatic install supported
- Developer
- Eclipse Adoptium
- Downloads via this site
This links to Eclipse Adoptium’s own download source. AfterFormat neither stores nor modifies installer files.
Check before installing
- This is not Oracle’s JDK. Oracle’s has separate commercial terms that catch companies out; this build has none.
- To only run Java programs a JRE is enough — and most modern software now bundles its own Java anyway.
What it is
The Java Development Kit distributed by Eclipse Adoptium. You need it to build Java programs or to run development tools written in Java. It is functionally the same as Oracle’s JDK but licensed differently, so there is nothing to check before using it at work.
When to pick this
If you develop in Java or use Java-based tooling. If a program tells you to "install Java", check which version it expects first.
Details
How it differs from Oracle’s JDK
Oracle’s JDK carries separate commercial terms that catch companies out. This build is GPLv2 with Classpath exception, with no such condition. Both come from the same OpenJDK source.
LTS release
This installs 21, a long-term support release. If a project pins a specific version, install that one instead.
JDK versus JRE
JDK is for building, JRE for running only. Most modern software ships with its own Java, so separate installs are rarer than they used to be.
After a reformat
JAVA_HOME and PATH
The installer sets PATH, but some tools also need the JAVA_HOME environment variable set by hand. With several versions, decide which is the default.
No settings to restore
It is a runtime with no user settings. Programs that run on Java (Minecraft and so on) are reinstalled separately.
Distribution
- winget ID
- EclipseAdoptium.Temurin.21.JDK
- Redistribution policy
- Open source licence
- Manifest checked
- 2026-10-23
- Official site
- https://adoptium.net/
The date the version and installer URL were checked in winget. This is separate from a usage-terms review or an installation test.
Original winget manifest
