ToolBoost Open editor

A JavaScript playground
with an AI pair

Test snippets, prototype ideas and debug JavaScript right in the browser. Console output appears instantly, and the AI can refactor or explain any line.

Start coding free →

No install · No account · Free

app.js
const users = [
  { name: "Ayu", age: 24 },
  { name: "Budi", age: 31 },
];

const names = users
  .filter(u => u.age > 25)
  .map(u => u.name);

console.log(names); // ["Budi"]

Features

Instant console output

Press Run and see console.log results, errors and return values immediately.

Ctrl+K inline edits

Select code, press Ctrl+K and describe the change — "convert to async/await", "add JSDoc".

Monaco editor

The same editor engine as VS Code: IntelliSense-style highlighting, multi-cursor and familiar shortcuts.

How it works

  1. Open the ToolBoost editor.
  2. Create a .js file.
  3. Write JavaScript and press Run — results appear in the output panel.

Tutorial: test JavaScript in seconds

A JavaScript playground is the fastest way to check how a method behaves, try an algorithm or debug a snippet from Stack Overflow. ToolBoost runs your code in a sandboxed frame and captures console.log, errors and warnings in the output panel.

1. Quick checks. Paste console.log([3,1,2].sort()) and press Run to see the result immediately.

2. Modern syntax. Arrow functions, destructuring, optional chaining, classes, async/await and fetch all work, because the code runs in your real browser engine.

3. Refactor with Ctrl+K. Select a block, press Ctrl+K and type an instruction like "convert to async/await" or "add error handling". The change appears as a side-by-side diff you can accept or reject.

4. Learn by asking. Highlight a line you don't understand — a regex, a reduce, a closure — and ask the AI chat to explain it step by step.

From snippet to project: add an index.html and style.css next to your .js file to turn the playground into a full web page with live preview, similar to JSFiddle or CodePen.

FAQ

Is this JavaScript playground free?

Yes, fully free with no account required.

Does it support modern JavaScript?

Yes — ES2023 syntax, async/await, classes and modules run in your browser.

Can I use it like JSFiddle or CodePen?

Yes. Combine HTML, CSS and JS files and preview them live.

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