Free JavaScript online compiler

JavaScript playground with a practice path

Experiment with JS quickly, pair it with regex and JSON tools, then prove fluency on the JavaScript coding track — not a compiler dead end.

JavaScript scratchpad

Free run — no login. Rate-limited. Same runner as the multi-language hub.

Source

const nums = [1, 2, 3, 5, 8];
console.log('Hello from Toolliyo Playground');
console.log('Sum =', nums.reduce((a, b) => a + b, 0));

stdin (optional)

Output

Press Run to execute.

After you try JavaScript

Frontend tutorials JS problems Problems explorer

Format, mock, or diff — then come back and re-run.

Regex Tester Validate patterns with live match highlights. JSON Formatter Pretty-print API payloads before you paste them into code. Code Diff Compare snippets side by side before you submit.

Does this support DOM / browser APIs?

This runner is for script logic (Node-style console output), not a full browser sandbox. Use coding practice and tutorials for front-end UI work.

Can I share my code?

Copy the snippet for now. For judged progress, submit on coding-practice problems instead.

Where do I go after the playground?

Toolbench utilities, then JavaScript coding problems or Skill Assess checkpoints.

Toolliyo Assistant

Ask about tutorials, ebooks, training, pricing, mentor services, and support. I use public site content only—not admin or internal tools.