Interactive Code Execution Visualizer

See How Your Code Really Works

Visualize code execution in real-time. Watch the event loop spin, memory allocate, pointers resolve, and the JVM garbage collect — all step by step.

playground.js

1console.log("Start");

2setTimeout(() => console.log("Timer"), 0);

3Promise.resolve().then(() => console.log("Promise"));

4console.log("End");

Everything You Need to Understand Code

More than a code runner — a visual learning tool that reveals the hidden mechanics of programming languages.

JavaScript, Python, C, C++, and Java — all in one playground.

Watch the JS event loop, microtask queue, and macrotask queue animate in real time.

See stack vs heap allocation, pointer relationships, and memory lifecycle for C/C++.

Breakpoints, call stack, variable inspection, and line-by-line stepping.

Beautiful dark and light modes with smooth transitions. Easy on the eyes.

Python GIL, Java JVM & GC, C++ RAII — see what happens under the hood.

Each language has its own engine-specific visualizations

Event Loop Animation

Call Stack Push/Pop

Microtask vs Macrotask Queue

Web APIs Tracking

Closure & Scope Chain