Tanmay Gupta

Posted on Jun 2

Creating Your First Express server

So you’ve heard of Express.js, the minimalist web framework for Node.js, and you’re ready to build your first backend server. Whether you're working on an API, a web app, or just want to learn backend basics, this blog post will guide you through creating your first Express server—step by step.

Prerequisites

Before we begin, make sure you have:

Node.js installed (v14+ recommended)
A code editor (like VS Code)
Basic knowledge of JavaScript

You can download Node.js from https://nodejs.org

Step 1: Create Your Project Directory

Open your terminal and run:
Or simply create and open that folder in vscode

mkdir my-express-server
cd my-express-server

Initialize a Node.js project:

npm init -y

This will create a package.json file with default settings.

Step 2: Installing Express

Now, install Express npm package:

npm install express

Step 3: Create Your Server File

Create a file named index.js:
or just create a new file in vscode using new file option

touch index.js

Step 4: Set Up the Server

In index.js, add the following code:

const express = require('express'); // requiring express
const app = express(); // create instance of express
const PORT = 3000; // port on which the server will run

// Root route
app.get('/', (req, res) => {
  res.send('Hello World! Your Express server is running 🎉');
});

// Start the server
// Listening to any requests that come on the defined PORT
app.listen(PORT, () => {
  console.log(`Server is running at http://localhost:${PORT}`);
});

Step 5: Run Your Server

In the terminal, run:

node index.js

If everything is set up correctly, you'll see:

Server is running at http://localhost:3000

Now open your browser and navigate to http://localhost:3000. You should see:

Hello World! Your Express server is running 🎉

Bonus: Use Nodemon for Auto-Restarts

Manually restarting the server every time you make a change can get annoying. Install nodemon for convenience:

npm install --save-dev nodemon

Update your package.json scripts:

"scripts": {
  "start": "node index.js",
  "dev": "nodemon index.js"
}

Now run:

npm run dev

Summary

In this tutorial, you:

Created a new Node.js project
Installed Express
Wrote a basic server
Tested it in the browser
(Optionally) used Nodemon for auto-restarts

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