CheerpJ is a JVM and a distribution of OpenJDK for the browser in WebAssembly and JavaScript. Now supporting Java 8, Java 11 and Java 17 (preview), with Java 21+ coming in 2026.
CheerpJ is a WebAssembly-based Java Virtual Machine and distribution of OpenJDK for modern browsers.
CheerpJ runs Java applications in modern browsers without a local Java installation. It ships a full OpenJDK environment and supports Swing and AWT UIs, plus frameworks such as Oracle Forms and Oracle EBS.
Removing local Java installs and legacy browser dependencies reduces client-side risk and support overhead.
CheerpJ runs existing Java clients in modern browsers, without a local Java installation and without plugins.
Start by running the current application from existing artifacts, then modernize in stages. Where it makes sense, replace parts of the client UI with web-native components while keeping the rest of the system intact.
CheerpJ is built on WebAssembly and includes a full OpenJDK runtime and an OS emulation layer for browser use cases.
CheerpJ lets web teams run Java libraries in the browser and call them from JavaScript. This supports architectures where web UI stays web-native, while proven Java components run client-side.
CheerpJ runs inside the browser sandbox and ships a full OpenJDK runtime compiled for the web.
The main CheerpJ tool for developers. A JVM / OpenJDK distribution in JavaScript and WebAssembly. Runs full Java apps and libraries in the browser.
An end-user tool to run Java Web Start apps in Chrome or Edge – without installing Java locally. Perfect for legacy enterprise applications.
An end-user tool to run Java Applets on modern browsers. Works instantly on Chrome or Edge, no code changes required.
Discover how to modernize and improve access to your legacy Java applications with CheerpJ.
Schedule a free demo with our team to learn how CheerpJ can help address your Java requirements.
Fill in the form or book a demo directly here
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