export default function App(): JSX.Element {
  return <h1>Hello world</h1>
}

Online React Compiler

What is React

React is a popular JavaScript library for building user interfaces. It uses components to encapsulate UI and behavior, allowing you to compose complex interfaces from small, reusable pieces. React's declarative model and virtual DOM make it efficient and predictable.

What is an online React compiler

An online React compiler provides a ready-to-run environment where you can write React components, compile JSX/TypeScript, and see the result instantly. It includes a code editor, live preview, and console to help you prototype React apps without local setup.

Want to learn React?

Take a look at our Complete Full-Stack Developer Roadmap, with in-browser code playground and interactive widgets to accelerate your learning.

We cover React with a structured learning path, bite-sized lessons, and real projects that build your skills and portfolio.