💡 Think you know the output? Try Code Challenges →
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Online Compiler & Code Playground

Multi-Language Sandbox

Write and run code online with a fast multi-language programming playground supporting Python, JavaScript, Java, C, C++, Kotlin, Swift, Dart and more.

Initializing Monaco Editor...
Ready
Click Run Code (Ctrl+Enter) to execute the script in an isolated sandbox.
Python 3.12.5 • Ln 1, Col 1
• Sandbox Secure
🔒 Privacy & Execution Sandbox: Code is sent securely to an isolated execution container when you press Run. Locally saved snippets remain strictly inside your browser's storage.
Zero login required

About the Multi-Language Online Compiler & Code Playground

Testing algorithmic snippets, experimenting with language syntax, or debugging code logic should not require setting up a local toolchain or Docker environment. This online compiler provides an instant, zero-login code editor and isolated execution playground supporting Python, JavaScript, TypeScript, Java, C, C++, Go, Rust, Kotlin, Swift, Dart, and more.

⚡ Fast Multi-Language Compilation

Run Python 3, modern C++ (GCC 13), Java 22, Go 1.23, Rust 1.82, Kotlin, Swift, and Dart against stable production compilers with standard input (stdin) support and precise timing metrics.

💻 Monaco Code Editor

Powered by the VS Code Monaco editor with full syntax highlighting, bracket pair colorization, line folding, keyboard shortcuts, tab-size adjustments, and multi-cursor editing.

🛡️ Secure Container Sandboxing

Executes programs inside ephemeral, hardened runtime containers with strict CPU time (5.0s) and memory (256MB) constraints, protecting against runaway loops and resource leaks.

Frequently Asked Questions

How is code compiled and executed?

JavaScript and TypeScript run immediately inside your browser's isolated Web Worker sandbox for zero network latency. Compiled languages like C, C++, Java, Python, Go, and Rust are submitted over HTTPS to isolated execution containers that compile and capture stdout/stderr output in real time.

Are my code snippets saved or public?

Your code is never shared publicly. Saved snippets are stored exclusively inside your local browser's IndexedDB storage. You can access your saved code anytime from the "Saved" menu or export files directly to your hard drive.

Can I test interview coding output questions?

Yes. If you are preparing for technical software engineering interviews, you can also explore our Code Output Quiz, featuring hundreds of verified questions across JavaScript, Python, C++, Java, Kotlin, and Swift.

Related developer utilities:
Programming Code Output Quiz → JSON Toolkit → Developer Text Toolkit → Developer Portfolio →
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