How to Send Emails in Node.js using Nodemailer and Ethereal

Email functionality is essential in modern web applications. Whether you're sending confirmation emails, password resets, or notifications, Node.js with Nodemailer makes this simple. In this blog, we'll walk through setting up email sending using Node.js, Express, and Ethereal Email for testing.

🧾 Prerequisites

• Node.js installed
• Basic knowledge of Express.js
• Internet connection

📁 Project Structure

project-folder/
├── index.js
├── .env
├── package.json
└── app/
    └── controller/
        └── emailSendController.js
  

📦 Step 1: Install Dependencies

npm init -y
npm install express nodemailer dotenv
npm install --save-dev nodemon

🔁 Configure nodemon (Optional but Recommended)

Update your package.json with a custom start script:

"scripts": {
  "start": "nodemon index.js"
}
  

🔐 Step 2: Create a .env File

Create a .env file at the root of your project to store sensitive info:

EMAIL_USER=mina.kshlerin89@ethereal.email
EMAIL_PASS=abffrpynHPC8RGarFW
PORT=3000
  

📨 Step 3: Build the Mail Controller

Create app/controller/emailSendController.js:

const nodemailer = require("nodemailer");
require('dotenv').config();

const sendMail = async (req, res) => {
  try {
    let transporter = nodemailer.createTransport({
      host: 'smtp.ethereal.email',
      port: 587,
      secure: false,
      auth: {
        user: process.env.EMAIL_USER,
        pass: process.env.EMAIL_PASS
      }
    });

    let info = await transporter.sendMail({
      from: `"Rana Saha 👻" <${process.env.EMAIL_USER}>`,
      to: "abcd@gmail.com, xyz@gmail.com",
      subject: "Node.js Email Test",
      text: "Hello! This is a test email.",
      html: "<b>This is a test email from a Node.js tutorial</b>"
    });

    console.log("Message sent: %s", info.messageId);

    res.status(200).json({
      success: true,
      message: "Email sent successfully",
      messageId: info.messageId,
      previewURL: nodemailer.getTestMessageUrl(info)
    });

  } catch (error) {
    console.error("Error sending email:", error);
    res.status(500).json({ success: false, message: "Failed to send email", error });
  }
};

module.exports = sendMail;
  

⚙️ Step 4: Create the Express Server

Create index.js:

const express = require("express");
const app = express();
require('dotenv').config();

const sendMail = require('./app/controller/emailSendController');

app.get("/", (req, res) => {
  res.send("Email Sending using Node.js");
});

app.get("/send-email", sendMail);

const PORT = process.env.PORT || 3000;

const Start = async () => {
  try {
    app.listen(PORT, () => {
      console.log(`🚀 Server is running on http://localhost:${PORT}`);
    });
  } catch (err) {
    console.error("Error starting server:", err);
  }
};

Start();
  

👨‍💻 Step 5: Run the Server

To start the server with nodemon:

npm start

Now visit http://localhost:3000/send-email to send a test email. If using Ethereal, you'll get a preview URL in the JSON response to view the fake email.

📎 GitHub Source Code

You can find the full working code in this GitHub repository:

https://github.com/RanaGithub30/Node-Email-Send

✅ Final Notes

• Use Ethereal for testing only. For production, use Gmail, Mailgun, SendGrid, etc.
• Keep your credentials secure using .env files and never commit them to version control.
• For sending attachments or templated emails, you can expand this controller further.

🎉 That's It!

You now have a fully functional Node.js email sending setup. Happy coding!