Skip to main content


Show more

Server-Side Rendering (SSR) with React.js

Server-Side Rendering (SSR) with React.js

Server-Side Rendering (SSR) in React.js involves rendering React components on the server and sending the generated HTML to the client, providing faster initial page loads and improved search engine optimization (SEO). SSR enables the browser to receive fully-rendered HTML content, making the application more accessible to search engine crawlers and improving performance for users with slower network connections. Here's how to implement SSR with React.js:

1. Setting up a Node.js Server

Start by setting up a Node.js server to handle HTTP requests and render React components on the server. You can use frameworks like Express.js or Next.js for server-side rendering.

Example using Express.js:

// server.js
const express = require('express');
const React = require('react');
const ReactDOMServer = require('react-dom/server');
const App = require('./App').default;

const app = express();

app.get('/', (req, res) => {
  const html = ReactDOMServer.renderToString(React.createElement(App));
  res.send(`<html><head><title>React SSR</title></head><body>${html}</body></html>`);

app.listen(3000, () => {
  console.log('Server is running on port 3000');

2. Rendering React Components

Use ReactDOMServer's renderToString() method to render React components to a string on the server. This method generates HTML markup for the specified component, including its children, and returns it as a string.


// App.js
import React from 'react';

const App = () => (
    <h1>Hello, SSR!</h1>
    <p>This is a server-side rendered React application.</p>

export default App;

3. Hydration on the Client

On the client-side, use ReactDOM's hydrate() method to attach event handlers and reattach React components to the server-rendered HTML. Hydration ensures that the client-side JavaScript takes over the server-rendered content without re-rendering the entire DOM.


// client.js
import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';

ReactDOM.hydrate(<App />, document.getElementById('root'));

4. Conclusion

Server-Side Rendering (SSR) with React.js offers several benefits, including improved initial page load times, better SEO, and enhanced performance for users. By rendering React components on the server and hydrating them on the client, you can create fast, SEO-friendly web applications with React.js.