Java Compiler Online — Compile & Run Java Code Instantly

Source Codemain.java
19 lines

Loading editor...

Terminal Ready

Click the Run button or press Ctrl+Enter to execute your Java program.

Java Online IDEOpenJDK 22

About the Online Java Compiler

Code Visualizer’s online Java compiler lets you write, compile, and execute Java programs directly in your browser — no JDK or IDE setup needed. Paste your class, hit Run, and see standard output, compilation errors, and runtime exceptions immediately.

The editor supports full Java syntax highlighting, IntelliSense autocompletion (toggleable), bracket matching, and code folding. Perfect for learning Java, practicing for interviews, testing OOP concepts, or running quick experiments.

Instant Execution

Run Java code in your browser with zero installation, zero environment setup, and zero dependencies.

Toggleable Suggestions

Full Monaco IntelliSense autocomplete, bracket matching, and syntax error alerts that can be toggled on/off at will.

Interactive Stdin

Pass interactive test input to your algorithms and competitive programming solutions via the Stdin tab.

Visualizer Bridge

One click opens your code inside our step-by-step memory visualizer to inspect stacks, heaps, and pointers.

Frequently Asked Questions

Write your Java code (with a class containing a main method) in the editor and click Run. The compiler compiles and executes your code, showing output and any errors in the output panel.