NodeMailer NPM Tutorial

NodeMailer is a popular NodeJS package for sending and receiving emails. It’s open source and has no external dependencies! Let’s see it in action:

NodeMailer requires access to an SMTP server, if you don’t have access to one or need a frontend solution try MailSlurp’s email API

Installing NodeMailer

First create a new NodeJS project with npm init -y.

Then install NodeMailer from NPM with npm install --save nodemailer.

Next setup your SMTP connection

Import nodemailer package and create a new instance.

const nodemailer = require("nodemailer");

Then connect your SMTP server:

const transporter = nodemailer.createTransport({
  host: "your-smtp-server",
  port: 587,
  secure: false,
  auth: {
    user: "smtp-user"
    pass: "smtp-password"

Note: if you don’t have access to an SMTP server use MailSlurp instead!

Sending emails

You can send emails as follows:

let info = await transporter.sendMail({
  from: "",
  to: ",",
  subject: "Hello",
  text: "Hello world",

What about receiving email?

Unfortunately NodeMailer can’t easily receive emails but there are tons of email APIs out there to help.

With MailSlurp you can create test email addresses then receive emails in Javascript using them. Let’s see it in action:

npm install --save mailslurp-client

Then create an inbox and wait for emails to be received.

const MailSlurp = require("mailslurp-client").default;
const inbox = await mailslurp.createInbox();
const email = await mailslurp.waitForLatestEmail({ inboxId:, timeout: timeout });

// { body: "Hello world", subject: "Hello", }

Use SMTP servers with MailSlurp


Creating inboxes

You can create SMTP mailboxes in Javascript using MailSlurp.

const inbox = await mailslurp.createInbox({ inboxType: 'SMTP' });