Have you ever wondered why developers use React alongside Node.js? Well, considering both React and Node.js are written in JavaScript, both seem to be the sensible choice for each other. However, in web development, we must go beyond convenience and use technologies that help us implement features we need in our solution.

In this article, we will discuss the connection between React.js and Node.js and find out when it’s ideal to use them together.

React.JS: When Do We Use It?

Created by Meta and now governed by the React Foundation under the Linux Foundation, React.js is a JavaScript library for building user interfaces. It started as a browser-based front-end library, but it can now also render on the server, and it pairs with almost any backend, from Node.js to Rails or PHP.

React.js was initially designed to work in web browsers. Unsurprisingly, it has a ReactDOM library built specifically to work alongside the browser’s DOM. The same component model also powers React Native, which brings React to iOS and Android.

React is perfect for building web apps and resolving issues related to low performance caused by DOM manipulation, as well as slow user interactions. It uses a Virtual DOM to save changes. At the same time, the library leverages an algorithm that analyzes the application’s state and figures out the difference between two UI states. Modern React also supports Server Components and streaming, which move more rendering work to the server and send less JavaScript to the browser.

Because of its dynamic nature, hiring React.js developers becomes the first choice for those who want to build highly robust native and hybrid applications.

Node.js: When Do We Use It?

Node.js is a highly scalable JavaScript runtime that lets you run JavaScript outside the browser, most often on the backend. The technology is known to be fast, lightweight, and asynchronous. Being event-driven, it has non-blocking I/O, making it easier for web apps to handle real-time data streaming.

Additionally, it is ideal for building modern solutions that rely on WebSockets, event queues, and microservices. Thanks to this flexibility, Node.js is also one of the most widely used web technologies in Stack Overflow’s Developer Survey, with close to half of respondents using it.

What makes Node unique is that we can use a single language, JavaScript, for both backend and front-end code. With TypeScript, teams can also share types and validation logic between client and server, which cuts bugs at the boundary between the two. With giants like Netflix, PayPal, NASA, and Walmart using Node.js for backend development, Node.js is understandably one of the best server-side options.

Node.js and React.js Comparison: What Makes Them a Good Couple

To start, both React and Node.js are JavaScript technologies, so you can use one language across the server and the client. That makes Node.js one of the easiest platforms to use with React.js. It conveniently lets us host and run a web server for React applications. Two things contribute to making that possible.

Firstly, Node leverages the Node Package Manager (NPM) to work with the NPM registry, allowing you to install any package you want using the NPM CLI. Node.js also powers the build tooling around React. Modern bundlers such as Vite and esbuild (and Webpack in older projects) run on Node.js to compile, bundle, and optimize a React app. Today, most new React projects start from a framework such as Next.js or React Router, or a Vite setup, rather than Create React App, and all of them run on Node.js.

Additionally, you can use the Node.js environment directly to execute React code. At the same time, React DOM’s server APIs are designed to work seamlessly with Node.js, making server-side rendering possible with fewer lines of code.

Server-Side Rendering (SSR) is a special feature of JavaScript applications where you can render your web application on the server instead of rendering it on the browser. Considering in-browser rendering is what React.js is known for, it’s easy to question why server-side rendering would be useful for React.js.

Well, to begin with, SSR can help your website attain a faster first page load time, contributing to a good user experience. Moreover, as web developers, you must understand the importance of SEO in data extraction and crawling. Search engines have gotten better at rendering JavaScript, but server-rendered HTML is still faster to index reliably and gives users a faster first paint.

Additionally, since search engines favor websites and apps with faster load times, loading client-side isn’t ideal for speed. Server-side rendering helps you get around all these problems and allows you to easily gather the metadata.

Apps exclusively rendered on the browser are excellent for managing user interaction effectively after the first page has loaded. Because Node.js enables React.js apps to implement Server-Side Rendering, they can hit the sweet spot in the middle and generate pages on the server side. In practice, most teams don’t wire up SSR by hand. Frameworks like Next.js and React Router run on Node.js and handle server rendering, streaming, and routing out of the box.

What makes this unique is that you can still manage all user interactions on the client side once your page has been loaded. Even in cases where changing your React app backend to Node.js isn’t feasible, you can still benefit from its multiple features. In these cases, Node.js can run the web server hosting your React application.

Node.js offers a range of highly efficient and reliable tools you can leverage without using the Node web server. If your backend is built in another language such as Python, Java, or Ruby, Node.js can still run the build tooling for your React front end.

When Is It Best to Choose Node.js with React.js?

Although using Node.js every time you create a React app isn’t necessary, there are many situations where these two bond perfectly with each other. They allow you to pull off major feats and make development significantly easier. Here are some of the situations where you should use Node.js with React.js.

MERN Stack

Node.js is the missing link of the MERN stack, so it only makes sense to use it alongside React.js when you’re also using MongoDB and Express.

Single Page Applications (SPA)

Node.js’s fast, lightweight nature, combined with asynchronous data loading through promises and async/await, makes it the perfect backend for developing Single Page Applications in React.

High Server Load

Node.js’s non-blocking, event-driven model handles many concurrent connections efficiently, which suits React apps that sit in front of busy APIs.

Real-Time Data

If you’re creating applications with core functions like data streaming, Node.js is excellent for maintaining persistent server connections.

JSON APIs

Node.js has high code reusability and smooth code sharing with React.js, so developing JSON APIs can be extremely efficient. This is especially true with TypeScript, where types and validation can be shared across client and server.

Full-Stack React with Next.js

Frameworks like Next.js let you build the UI, server rendering, and API routes in one codebase running on Node.js. It’s a popular choice for teams that want React’s front end and a Node backend without managing two separate projects.

Both Node.js and React have been designed for different purposes and are ideal for specific use-cases. However, when combined, these technologies make your web applications robust, powerful, and highly scalable.