Your Java applications still work.
CheerpJ makes sure they keep working.
Rewriting critical systems is expensive, risky, and rarely necessary. CheerpJ runs Java applications in the browser, preserving your investment while simplifying deployment.
Choose a starting point based on your application architecture, delivery model, or transformation strategy.
Run Oracle Forms and EBS
Access Oracle Forms and EBS in modern browsers without plugins, desktop installs, or Java dependencies.
Replace Citrix / VDI
Run Java applications directly in the browser without virtual desktops, remote sessions, or infrastructure overhead.
De-risk Java rewrites
Maintain access to legacy Java applications while building their replacement, without relying on desktop Java or VDI.
Run Java applications in the browser
Deliver existing Java applications through the browser without plugins, installs, or application rewrites.
How to
Evaluate
CheerpJ
Validate browser compatibility, runtime behaviour, and deployment requirements before production rollout.
Request a Compatibility ReviewShare application details
Java version, deployment model, UI framework, dependencies, authentication, and browser requirements.
Compatibility review
Runtime, networking, security, file access, native dependencies, and JNI assessment.
Technical validation build
Test startup behaviour, workflows, authentication, browser support, and deployment requirements.
Production deployment
Move into rollout planning, user acceptance testing, hosting, security review, and production support.
How CheerpJ runs Java applications in the browser
CheerpJ runs standard Java applications directly in the browser using WebAssembly. It provides a full OpenJDK runtime and Java Virtual Machine that executes Java bytecode without plugins, desktop installations, or source code changes.
1. Java Runtime in the Browser
CheerpJ includes a full OpenJDK runtime compiled to WebAssembly and JavaScript. It supports Java 8, Java 11, and Java 17 applications and runs entirely inside modern browsers.
3. Interpreter + JIT Optimization
Java bytecode starts in an interpreter, while frequently used code is compiled Just-in-Time into optimized JavaScript for higher performance.
2. JVM Executes Java Bytecode
Applications are loaded as standard JAR, class, or WAR deployments. CheerpJ executes the bytecode using a browser-based Java Virtual Machine.
4. Browser Integration Layer
CheerpJ provides system services needed by enterprise applications, including virtual file system support, HTTP networking, Java ↔ JavaScript interoperability, and AWT/Swing rendering through HTML Canvas.
Easily deploy CheerpJ
CheerpJ is delivered as static WebAssembly and JavaScript assets. It can be hosted on any web server or CDN and integrated into a page with a simple <script> tag. No browser plugins or server-side components are required.
Enterprise Java compatibility
CheerpJ provides a browser-based JVM built on OpenJDK, with full Java language compatibility and bytecode-level execution. Supports standard JAR and WAR deployments, including Swing and AWT applications, without requiring a client-side JVM.
Java Versions
✔️ 8, 11, 17 (preview)
✔️ Java bytecode execution in the browser
✔️ Full Java runtime delivered client-side (WebAssembly-based)
✔️ Use for long-running applications that are difficult to rewrite
UI and graphics
✔️ Standard Swing/AWT widgets
✔️ Multiple windows within the application UI
✔️ Typical enterprise UI workflows (forms, tables, dialogs)
Networking
✔️ HTTP/HTTPS networking
✔️ Backend services remain unchanged
✔️ Works with existing application APIs and service endpoints
Deployment
✔️ On-premise
✔️ Controlled enterprise environments
Explore our Java execution tools for the browser
CheerpJ Core
The main CheerpJ tool for developers. A JVM / OpenJDK distribution in JavaScript and WebAssembly. Runs full Java apps and libraries in the browser.
CheerpJ JNLP Runner
An end-user tool to run Java Web Start apps in Chrome or Edge – without installing Java locally. Perfect for legacy enterprise applications.
CheerpJ Applet Runner
An end-user tool to run Java Applets on modern browsers. Works instantly on Chrome or Edge, no code changes required.
Request a demo
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