React – How to Start Server

When developing a React application, you often use a development server to preview changes in real-time. This tutorial explains how to set up and start a React development server using Create React App (CRA), the most common tool for React projects.

Prerequisites

Ensure Node.js and npm (Node Package Manager) are installed on your system. You can download them from nodejs.org.

Basic knowledge of using a terminal or command prompt is required.

Steps to Start a React Server

Step 1: Create a New React App. If you don’t have a React application, you can create one using the Create React App CLI tool. Run the following command:

</>
Copy
npx create-react-app myapp

This will create a new React project in a folder named myapp.

Step 2: Navigate to the Project Directory. Change your working directory to the newly created project folder:

</>
Copy
cd myapp

Step 3: Install Dependencies. Ensure all necessary dependencies are installed by running:

</>
Copy
npm install

Step 4: Start the Development Server. Start the React development server using the following command:

</>
Copy
npm start

This will open your default web browser and load the React app at http://localhost:3000.

Start React Server using npm start command

Customizing the Development Server

By default, the React development server runs on port 3000. You can change this port or customize other settings:

To change the port: Set the PORT environment variable before running the server:

</>
Copy
PORT=4000 npm start
Start React Server on Port 4000

Common Issues and Solutions

Issue: npx: command not found

Solution: Ensure that Node.js and npm are installed. Restart your terminal after installation.

Issue: Port 3000 is already in use

Solution: Use a different port by setting the PORT environment variable.

Issue: Browser doesn’t open automatically

Solution: Open http://localhost:3000 manually in your browser.

Conclusion

Starting the React development server is an essential step in the development process. With the npm start command, you can preview your application in real-time and make changes efficiently.