Online Java Compiler – Run Java Online (11, 17, 21)
Write, compile, and run code instantly in your browser. Our free online compiler supports 60+ programming languages including Python, Java, C++, JavaScript, Go, Rust, and many more. No installation required.
About Online Compiler
Our free online compiler lets you write, compile, and run code instantly in your browser. Supports Python, Java, C++, JavaScript, Go, Rust, and many more languages. No installation required.
Compare Languages Side by Side
Want to see how Java stacks up against another language? Open the Code Playground to run Java next to Python, Go, Rust, or any language — each pane picks its own language and version, and you run them together.
Supported Languages
Popular: Python, Java, C++, C, JavaScript, TypeScript, Go, Rust
Web: PHP, Ruby, Node.js, HTML/CSS
Systems: C, C++, Rust, Go, Swift
Functional: Haskell, Scala, Kotlin, F#, Clojure
Features
- Monaco Editor (VS Code) with syntax highlighting
- Real-time code execution with output streaming
- Custom compiler flags support (-O2, -Wall, etc.)
- Share code via unique snippet URLs
- Keyboard shortcuts (Ctrl+Enter to run)
Run Java Online (11, 17, 21)
Compile and run Java online using LTS versions 11 and 17, or the latest 21. Supports multi‑file projects.
FAQ
Which Java versions are available? Java 11, 17, and 21 are available.
How do I set the main class? Use a file named Main.java with public static void main.
How do I share code? Click Share to get a snippet URL.
How to Use Online Compiler
Choose from 60+ programming languages including Python, Java, C++, JavaScript, Go, Rust, and more.
Use our Monaco editor (same as VS Code) with syntax highlighting, auto-completion, and error detection.
Click Run or press Ctrl+Enter. Your code executes in a secure sandbox and output appears instantly.
Share your code via unique URL or embed interactive code snippets in your blog, book, or documentation.
For Authors, Educators & Technical Writers
Perfect for programming books, online tutorials, technical documentation, and educational content. Embed interactive, runnable code examples directly in your content.
Click Embed button above to generate embed code for your content!
Example: Hello World in Python
# Simple Python example - try it above!
def greet(name):
return f"Hello, {name}!"
print(greet("World"))
print("Welcome to 8gwifi.org Online Compiler")
# Output:
# Hello, World!
# Welcome to 8gwifi.org Online CompilerCopy this code into the editor above and click Run to see it in action!
Popular Online Compilers
Jump straight to a language-specific page:
Need embeds? See Embed Online Compiler.