Online Code Compiler
Compile and run Python, JavaScript, Java, C, C++, and PHP directly in your browser. Real-time stdout/stderr, interactive stdin, and fullscreen IDE mode.
Sandboxed Isolation
Every execution runs in an ephemeral, isolated sandbox with strict timeouts and automatic cleanup. Fast, secure, and private.
Interactive stdin Streams
Feed custom input data directly into your programs. Compatible with Python input(), C scanf(), C++ cin, and Java Scanner.
Fullscreen IDE Mode
Immerse yourself in a distraction-free development environment. Supports hotkeys including Ctrl+Enter to run and Esc to exit.
Supported Programming Languages & Sandboxed Execution
The C³ MindLoop Online Code Compiler runs a multi-language hybrid execution engine. High-performance runtimes compile and execute your source code in an isolated environment with zero software installation required on your computer:
| Language | Runtime / Compiler | Execution Mode | Default Entry Point |
|---|---|---|---|
| Python | CPython 3.12 / 3.14 | Native / Isolated Sandbox | main.py |
| JavaScript | Node.js v20+ (V8 Engine) | High-Speed Local Runner | main.js |
| Java | OpenJDK 21 LTS | Javac + JVM Container | Main.java |
| C | GCC 13 / 14 (-lm) | Compiled Native Binary | main.c |
| C++ | G++ 14 (-std=c++17) | Compiled Native Binary | main.cpp |
| PHP | PHP 8.3 (Zend Engine) | CLI / Isolated Sandbox | main.php |
Keyboard Shortcuts & IDE Productivity Features
Execute CodeCtrl + Enter
Trigger instant code compilation and execution directly from the code editor without touching the mouse.
Fullscreen ModeEsc (Exit)
Expand the compiler into a distraction-free full-screen IDE experience. Press the Fullscreen button or hit Esc to return.
Smart IndentationTab
Inserts a standard 2-space tab character instead of shifting focus away from the code editor area.
Interactive Standard Input (stdin) & Terminal Streams
Interactive programs expecting user input (e.g. Python input(), C scanf(), C++ cin, Java Scanner, or PHP fgets(STDIN)) are fully supported via the stdin toggle panel.
Standard Output (stdout)
Successful output is captured and rendered with clean green syntax highlighting in the terminal window, including runtime execution duration in milliseconds.
Standard Error & Diagnostics (stderr)
Syntax errors, compiler diagnostics, and uncaught runtime exceptions are isolated in a dedicated error panel with non-zero exit codes to make debugging effortless.
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