Sending emails from web applications is a fundamental aspect of modern web development. Whether it’s sending notifications, newsletters, or transactional emails, integrating email functionality into your web application is essential. In this comprehensive guide, we’ll explore how to seamlessly incorporate Nodemailer, a robust Node.js module for sending emails, into your existing Express.js application. By leveraging Nodemailer’s capabilities alongside Express.js, you can enhance your application’s communication capabilities and provide valuable features to your users.


Before diving into the tutorial, ensure you have a solid understanding of the following:

– Basic concepts of Node.js and Express.js

– Familiarity with npm and package management

– A functional Express.js application set up and running on your local machine

1. Installing Nodemailer:

Nodemailer simplifies the process of sending emails from your Node.js applications. Begin by installing Nodemailer as a dependency in your project

npm install nodemailer

Nodemailer supports various email services and protocols, making it flexible for different use cases. You can configure it to work with SMTP, sendmail, or even third-party email providers like Gmail or SendGrid.

2. Configuring Nodemailer:

After installing Nodemailer, you’ll need to configure it to connect to your desired email service provider. For instance, if you’re using Gmail, you can set up Nodemailer to utilize Gmail’s SMTP server for sending emails. Here’s an example configuration:

const transporter = nodemailer.createTransport({
service: ‘gmail’,
auth: {
user: ‘’,
pass: ‘your-password’

Ensure you replace `’’` and `’your-password’` with your actual Gmail credentials. It’s recommended to use environment variables to store sensitive information securely.

3. Creating an Email Template Using EJS:

EJS (Embedded ) is a popular templating engine for generating HTML with dynamic content. We’ll leverage EJS to create reusable email templates. Begin by installing the EJS package:

npm install ejs

Then, create an email template file (`email.ejs`) within a `views` directory. This template will serve as the structure for our email content, allowing us to inject dynamic data such as recipient names and image URLs.

<!– views/email.ejs –>
<title>Email Template</title>
<h1>Hello <%= recipientName %>,</h1>
<p>This is a sample email with an image.</p>
<img src="<%= imageUrl %>" alt="Sample Image" />

By using EJS, we can easily customize the email content and include placeholders for dynamic data.

4. Creating a Route for Sending Emails:

In an Express.js application, routes define the endpoints that handle incoming requests. Let’s create a route specifically for sending emails. This route will extract necessary information from the request body, such as the recipient’s email address and the email subject, and use Nodemailer to send the email.

“`‘/send-email’, (req, res) => {
const { to, subject } = req.body;

const mailOptions = {
from: ‘’,
to: to,
subject: subject,
html: ejs.renderFile(__dirname + ‘/views/email.ejs’, {
recipientName: ‘John Doe’,
imageUrl: ‘’

transporter.sendMail(mailOptions, (error, info) => {
if (error) {
console.error(‘Error sending email:’, error);
res.status(500).send(‘Error sending email’);
} else {
console.log(‘Email sent:’, info.response);
res.send(‘Email sent successfully’);

This route handles POST requests to the `/send-email` endpoint. It extracts the recipient’s email address and subject from the request body, renders the email template using EJS with dynamic data, and sends the email using Nodemailer.


In this comprehensive guide, we’ve covered the process of integrating Nodemailer into your existing Express.js application to enable email sending functionality. By following these steps, you can enhance your application’s communication capabilities and provide valuable features to your users. Experiment with different email templates, content, and configurations to tailor the email sending process to your specific use cases and requirements. With Nodemailer and Express.js, you have the tools to deliver dynamic and engaging emails seamlessly from your web application.