JavaScript Visualizer

Interactive visualizations of core JavaScript concepts

Sample Code

console.log("1");

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

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

console.log("4");

Visualization

Step 1 / 8

Initial state — code starts executing

Call Stack

Empty

Web APIs

Empty

Microtask Queue

Empty

Callback Queue

Empty

→ Web APIs handle async

Microtaskshave priority overCallbacks