Back to Articles
JSX
React
JavaScript
Web Development
Frontend Frameworks
Coding
UI Components

What is JSX and How Does It Work in React?

Praveen Kumar
August 21, 2025
• 3 min read
What is JSX and How Does It Work in React?

What is JSX?

JSX is a special way to write HTML in JavaScript. It helps to make user interfaces for websites easier to create. With JSX, you can mix HTML and JavaScript in one place. This keeps your code neat and clear, which makes it simple to build and understand your website's layout.

Why Use JSX?

Here’s the thing: JSX allows developers to write code that looks a lot like HTML, but it works inside JavaScript. This can help you save time because you don't have to switch back and forth between HTML and JavaScript files. Instead, you write everything together. Below are some key reasons to use JSX:

  • Easier to Read: JSX looks like HTML, so it's easy for developers to read and understand the code.
  • Mixing Languages: You can combine HTML and JavaScript in one component, which makes working on different tasks more straightforward.
  • Useful Features: It supports JavaScript expressions, functions, and variables, allowing for dynamic content.

How Does JSX Work?

JSX is not the same as HTML. It's a syntax extension for JavaScript. When you write JSX, it gets transformed into regular JavaScript by a tool called Babel. This means that browsers can understand it. Here’s how this transformation works:

const element = <h1>Hello, world!</h1>;

In the code above, we create a JSX element. Babel will convert this to a regular JavaScript function call. It will look something like this after transformation:

const element = React.createElement('h1', null, 'Hello, world!');

What this really means is that JSX is just a way to write these React.createElement calls more easily. It makes your code cleaner and easier to handle.

Embedding JavaScript in JSX

One of the nice features of JSX is that you can embed JavaScript directly within your HTML-like code. You do this by using curly braces. Let’s see an example:

const name = 'Alice';
const greeting = <h1>Hello, {name}!</h1>;

In this example, we are using the variable name inside JSX. When the component renders, it will show Hello, Alice!. This ability to embed JavaScript is what makes JSX so powerful.

JSX and React

JSX is often used with React, a popular JavaScript library for building user interfaces. While you can use JSX without React, it shines best when combined with it. React components can return JSX, letting you create complex UIs simply and effectively.

Getting Started with JSX

If you want to try out JSX, you can set up a React project easily. You can use tools like Create React App to get started quickly. Here’s how you can do it:

  1. Make sure you have Node.js installed on your computer.
  2. Open your terminal and run the following command:
npx create-react-app my-app
  1. Navigate to your new project folder:
cd my-app
  1. Start the development server:
npm start

Now, you can open the src/App.js file and start writing some JSX. Here is a simple example you could add:

function App() {
  return <div><h1>Welcome to My App!</h1></div>;
}

Final Thoughts

JSX is a useful tool for anyone working with React. It makes writing code simpler and keeps everything in one place, which is great for maintaining clarity. Sure, there might be a small learning curve at first, but once you get the hang of it, you'll find that JSX is a powerful way to build interfaces.

To dive deeper into JSX, you can check the official documentation on React's website. Happy coding!