Published: Jan 1, 2024

Top 7 React App Optimization Techniques for 2025

Q: What are the different tools for improving React performance?

Understanding React performance tools is essential if you want to help developers analyze app performance, enhance certain elements of their projects, and do much more. The list of the tools: 1. React Profiler: It helps in improving React performance by identifying and optimizing performance bottlenecks in your app. With an insight into component render times, it helps to optimize for a better user experience. 2. Bit.dev: By enabling component driven development and modularization, the tool allows one to craft reusable and optimized React components. This makes managing and improving the performance of your app simpler. 3. Why-did-you-render: The tool's primary function is to alert developers to any needless re-renders in their React or React Native code.

Q: Why is my React app slow to load?

One of the foremost reasons of slow React applications is the inefficient rendering of the components. React makes use of the Virtual DOM to compare and analyze the current and the new state of the application, and then updates the actual DOM whenever required. Yet again, if the component is re-rendered without specific reasons, it causes performance issues.

Q: How to measure the performance of React app?

To measure the performance of React apps, you can make use of tools like React Profiler, Bit.dev, or browser developer tools. With the help of these tools, you will get an insight into component render times, network requests, and overall performance.

Faisaluddin Saiyed

Verified Expert in Project management

Faisaluddin is a Project Lead passionate about successful software delivery.

Expertise:

React JS Node JS PHP DevOps

React Performance Optimization Techniques

Quick Overview: Have you been surfing the web to look for different ways to help your React application perform well? If so, you’ve landed on the right page! Strap in as we will walk you through the top performance techniques for React to help you stay ahead. Read on the write-up and learn about different approaches that will help you to ensure that your React app performs in the best possible ways.

Do you ever sit back and wonder why big names like LinkedIn, Dropbox, and CSDN use React, especially for their web applications?

Of course, a few of you must quote that it is a popular JavaScript library, yet again, you need to know that there is a lot more to it. Wondering what are we talking about or referring to? We are pointing at the set of benefits that it brings to the table.

The list of perks includes - it builds more quickly than competing libraries, saving you time when creating your app or website. It should go without saying that no business likes wasting their valuable time.

With that being said, let us walk you through the best performance optimization methods and how ReactJS development solutions from a leading provider can help you with it. Without ado, let’s dive into the techniques.

On This Page

Introduction: How React Updates Its UI
React Performance Optimization Techniques
Conclusion

Introduction: How React Updates Its UI

Before dwelling into the realm of the leading performance optimization methods for React, let us take an in-depth insight and understand how React updates its UI and how you should measure the app performance.

First, if you have been using React or even if you are a beginner and have started learning it, you must have come across the term ‘Virtual DOM,’ right?

What is this, and why does React use it?

The Virtual DOM is a programming concept in which an ideal or virtual UI representation is kept in memory and synced with real DOM by a library such as ReactDOM.

Well, moving ahead, React produces a Virtual DOM for the component's element tree when a displayed component is created. React recreates the Virtual DOM tree whenever the component's state changes and compares the outcome with the previous render. It just uses diffing to update the altered element in the DOM.

Do You Want an In-Depth Insight on Optimization Techniques for React Apps?
Contact Our Experts

React Performance Optimization Techniques

Optimizing performance in React applications is essential for creating a smooth and responsive user experience. Here are several techniques to enhance the performance of your React apps -

1. List Virtualization in React Apps

If your application renders a long list of data, it is highly recommended to use an ultimate approach called ‘windowing’. The method can significantly minimize the time it takes to re-render the customized DOM nodes and components because it only renders a very tiny subset of your rows at a time.

Moving ahead, React-window and React-Virtualized are two windowing frameworks that are available. They offer several reusable components for lists, grids, and tabular data displays. Additionally, if you require something more specifically tailored to the intended usage of your application, you may even design your own windowing component, just like Twitter did.

2. Make Use of React.Fragment to Avoid Adding Extra Nodes to the DOM

React fragments serve as a cleaner alternative to using unnecessary division in the code. Since the fragments don't add any new elements to the DOM, their children will simply render without the need for a wrapper DOM node.

There are instances in React where you'll need to render many elements or deliver a collection of related objects. Are you curious arebout what we're referring to? Let's examine the illustration.

function App() {
return(
<h1>Welcome React! </h1>
<h1>Welcome React Again! </h1>
</div>
);
}

An error message reading "Adjacent JSX elements must be wrapped in an enclosed tag" will be displayed if you use this code. As a result, you will need to include both the elements inside the parent div.

Even if it will fix the problem in the best way possible, you should be aware that there is a risk involved. In this case, the DOM gains an additional node. A problem arises in these situations when a child component is encased within the parent component.

One of the best ways to solve this problem is that you consider using React Fragment which will not add an additional node to the DOM.

Function Columns ()
{
Return (
<React.Fragment>
<td> Welcome React! </td>
<td> Welcome React Again! </td>
<React.Fragment>
);
}

Craft A1 React Native Applications with the Leading Professionals and Shorter Development Cycles
Give It a Shot!

3. Make Use of React.Suspense and React.Lazy for Lazy Loading Components

It is rightly said, “never load more code than necessary to your users.”

Do you ever wonder why that is? Well, the reasons are straightforward: giving your end users superfluous code can cause performance leaks.

Let's now examine why Lazy Load is so effective.

Simply put, a React application can expand easily. Several components can be added, and these components can each include anywhere from 10 to 500 lines of code.

Now, loading every component, even if the end users do not need it, may impact the overall performance of your React application and the user experience.

Load component without Lazy Load

import React from 'react';
import GalleryComponent from './GalleryComponent'

const HomeComponent = () => (
<div>
<GalleryComponent />
</div>
)

Load component with Lazy Load

import React, { lazy } from 'react';
const GalleryComponent = lazy(() => import('./GalleryComponent'));

const HomeComponent = () => (
<div>
<GalleryComponent />
</div>
)

By now, you must have a clarity that the addition of Lazy Load is simple and extremely worth it.

Now let us walk you through the lazy Load and Suspense Combination.

Knowing how Lazy Load functions and how it may improve the user experience and performance of React applications, you must be wondering why we also need Lazy Suspense.

To understand the same, let us get started by considering and looking at an example, one like we have used before.

This time, let us consider that <GalleryComponent /> contains one of the problems like: API requests that take a few seconds to return a result, weaker devices, bad network connection, or large JavaScript payload.

import React, { lazy } from 'react';

/*
- GalleryComponent contain API request / large JavaScript payload.
*/
const GalleryComponent = lazy(() => import('./GalleryComponent'));

const HomeComponent = () => (
<div>
<GalleryComponent />
</div>
)

It goes without saying that this command is poor for the user experience because there is a risk that the user may see a blank area for a few seconds while waiting for the <GalleryComponent/> to respond. This is where React Suspense enters the picture.

React Suspense works in the best possible ways to display components to the users that depict the users that the component is loading at the moment, so that the users see that message while there’s a delay in loading. Isn't that great? It is, right!

import React, { lazy, Suspense } from 'react';

const GalleryComponent = lazy(() => import('./GalleryComponent'));

const renderLoader = () => <p>Loading...</p>;

const DetailsComponent = () => (
<Suspense fallback={renderLoader()}>
<GalleryComponent />
</Suspense>
)

The suspense tends to receive a fallback component that will be displayed to the users while the loading delay. With this, the users will see “loading...” prompt while the <GalleryComponent />, is load.

Craft Modern Applications or Redefine Your Web Idea with #1 ReactJS Development Company
Let’s Get Started!

4. Use Production Build

Make sure to test any performance issues you may be seeing with your React apps using the production build's minified version.

React comes with a number of useful warnings by default. These cautions are quite important, especially when it comes to development. It's crucial that you utilize the production version, especially when deploying the project, as they have a tendency to make React bulkier and slower.

Well, if you are unsure about the setup of your build process, you can make the most out of React Developer Tools for Chrome to conduct a check. Moreover, when you visit the site with React in production mode, remember, the icon will have a dark background.

React in production mode with dark background

Also, if you visit the site when React is in development mode, the icon will have a red background.

React in production mode with red background

When it comes to working on your app, ensure that you make use of development mode. On the other hand, when releasing it to the users, you should use a production model.

*Note – Make sure to update React from development files to production-ready ones if you use React via CDN.

5. Make Use of React.memo for Component Memoization

‘The BBC found they lost an additional 10% of users for every additional second their site took to load – Google Developers.

Well, nobody likes slow websites, right? Why? Because it is a mere waste of time!

It also goes without saying that a website's popularity and income are influenced by how effective it is. Moving forward, it's just a matter of time before you run upon a method called memoization if you start to pay close attention to the performance optimization of your website. The majority of you must now be seeking what it is and how to use it.

Memorization is a technique for speeding up computer programs by caching the outcomes of pricey function calls and returning them when the same inputs are encountered again.

Now that you have an understanding of what is memoization, let us understand and look at how does it really works.

With the assistance of this method, a certain function is produced, and the result is saved in memory. When a function with the same parameter is called in the future, it provides the result-saving bandwidth.

Let's dive more into the same.

Functions are functional components in React, whereas arguments are props.

To make things clearer for you, here is an illustration.

import React from ‘react’;

Const MyComponent = React.memo(props => {/* render only if the props changed */});

6. Understand the Handling of ‘THIS’

Another React performance optimization techniques is to get the understanding of ‘This’

In case you are someone who’d wish to employ functional components, then one thing you need to understand is that it does not require THIS binding.

React will not automatically connect your functions within components if you are using ES6 binding, but you may still do it manually. Wondering how to do the same? Here are a few ways for you:

Render binding
Constructor binding
Arrow function in render
Bind arrow function in the class property

7. Make Use of Function in ‘SetState’

In SetState, it is recommended to use a function rather than an object. The same is recommended because state changes do not happen immediately, contrary to what the React documentation assumes.

Thus, instead of this:

this.setState({correctData: !this.state.correctData});

Use this:

this.setState((prevState, props) => {
return {correctData: !prevState.correctData});
}

This function will receive the previous state as its first argument, and the props at the time the update is applied as the second argument.

With that, we’ve completed our list of the top 7 performance optimization techniques for React apps! Well, the methods mentioned here must not all be implemented.

*Pro Tip – Remember to code the project first, and then optimize React app wherever needed.

Build Interactive React Apps with Top-Notch Skill Sets from Our Experts
Hire Professional React Developers Now!

Here’s more to it, a YouTube video on tips and tricks to optimize your React Applications, give it a shot! Well according to research by INC., 65% of the population are visual learners, so give the video a look!

ConclusionBy now, you must have an insight into the various React optimization techniques. You can follow these top 7 approaches shared in this write up to upgrade and refine the performance of your React applications.Yet again, if you find difficulty in adopting these techniques, then professionals from a trusted React Development Company, Radixweb, can help you with implementing these approaches. Our experts analyze and optimize rendering, reduce unnecessary re-renders, and optimize network requests. For more information on how to get started, contact our experts now!

FAQs

What are the different tools for improving React performance?

Why is my React app slow to load?

How to measure the performance of React app?

Faisaluddin Saiyed

Verified Expert in Project management

View All Posts

About the Author

Faisaluddin is a dynamic Project Orchestrator passionate about driving successful software development projects. His enriched 11 years of experience and extensive knowledge spans NodeJS, ReactJS, PHP & frameworks, PgSQL, Docker, version control, and testing/debugging. Faisaluddin's exceptional leadership skills and technical expertise make him a valuable asset in managing complex projects and delivering exceptional results.

Build Software Application to 3X Your Biz Growth

Name*

Email*

Country