JavaScript is a programming language that’s versatile, working for both front-end and back-end development. This article will guide you through using JavaScript on the client-side to send emails from an application without needing a back-end.

Using JavaScript for email transmission

When it comes to sending emails, JavaScript has its limitations — it can’t directly send emails due to its lack of support for server sockets. However, JavaScript is often used in conjunction with server-side languages to facilitate communication with SMTP servers. Together, they seamlessly communicate with SMTP servers, enabling the server script to send emails from the browser in response to user queries.

Why use Javascript to send emails?

Emails are typically sent from the server-side of a standard app, which requires a server setup using back-end technology. When a request is made from the client-side, the server receives it, creates an email, and sends it to the SMTP server.

Why then would you want to use JavaScript to send emails directly from the client side? Such a method is quite helpful for developing contact forms and other user interfaces for web apps since it enables email sending without requiring the user to reload the page they are currently viewing. Additionally, you don’t need to play around with server programming. If your web application solely sends emails in response to contact forms, this approach could also be appealing.

How to use JavaScript for client-side email sending

To enable client-side email sending in your app with JavaScript, you have several options:

Mailto: for delivering form data

You can program the browser to launch the default mail client to send an email directly through JS. Although it is not technically possible to send an email straight from a browser, the mailto: method can be used.

HTML example

See how the following piece of code functions:

You'll see the following when you open it in the browser:

gmail

Following the data submission, the browser launches the default mail client.

compose email

Although the mailto: method is a fairly simple implementation, it has the following specific drawbacks:

  • Given that the data is supplied in the form that the browser sends, you do not influence how the data is laid out.

  • Mailto: doesn't guard against spambots gathering your email address. A link might be built-in JS in the past to help with this. Nowadays, a growing number of bots use JS and do not solely rely on HTML produced by the server.

SmtpJS with a SMTP Server

A free package called SmtpJS can be used to send emails from JavaScript. To complete the task, an SMTP server and a few adjustments are required. Since mailslurp is a practical email testing solution, it serves as the server in this example. The procedure to follow is outlined below: Create an HTML file with the following script in it (for instance, test.html):

A button that will activate the JavaScript function should be created.

Create the JS function to use SmtpJS.com to send emails.

You can include an array of email addresses in the To: attribute if you have numerous recipients. Send emails by running “test.html” in the browser.

The problem with the code example above is that the client-side script makes your login and password visible. If you use the SmtpJS encryption option, you can resolve this. After completing the necessary fields, click the box that says "Encrypt your SMTP credentials." Following that, select Generate security token, and use it in your JS function in place of the following SMTP server settings:

An HTML email sample and an email with an attachment are shown below. This is how the email will appear in the recipient's inbox, thanks to mailslurp's GUI.

An example of HTML email coding:

Sample of the code needed to send an email with attachments Use the Attachments property to send an email with an attachment as shown:

Send emails without code

MailSlurp.com offers a hassle-free way to connect email providers, create email templates, and send emails directly from JavaScript, all without the need for server-side code. Whether you prefer to use personal services like Gmail or Outlook, or well-known transactional services like Amazon SES or Mailgun, MailSlurp has you covered.

Using MailSlurp’s built-in editor, you can easily create email templates and customize them to suit your needs. The editor offers a range of tools, including auto-reply and reCAPTCHA verification, making email creation a breeze. Once you’ve crafted your email, simply click “Save” to store it for future use.

One of MailSlurp.com’s standout features is its ability to conceal standard email characteristics, ensuring your emails look professional and legitimate. Since the recipient field is included in the template and cannot be changed using JS, you transmit the template that was previously set up. To get started, install the MailSlurp SDK using npm.

Via browser

You should insert the following code before the closing tag if you need to use mailslurp on your website:

Two techniques can be used to send the email itself:

  • mailslurp.send
  • mailslurp.sendForm.

mailslurp.send

mailslurp.sendForm

Let's send an email directly from the browser to see if mailslurp.com functions as expected. We have created a straightforward template and set up the mailslurp email service. Now, we must write the following code into an HTML file:

Try it out in your browser by opening the mailslurp Demo Inbox. It works!

However, there is a way to send emails without ever using a browser that is simpler and faster. After testing them, “mailslurp Email Delivery” enables you to rapidly authenticate your domain and send emails using SMTP or API.

To conclude

In this tutorial, we have explored how JavaScript, in conjunction with Node.js, can be used to send emails directly from the client-side. By leveraging JavaScript’s capabilities, developers can create dynamic and interactive email features within their web applications. Whether it’s using the mailto: method for simple form data delivery or utilizing packages like SmtpJS for more advanced email sending, JavaScript offers a range of options for client-side email transmission.

Additionally, services like MailSlurp provide convenient solutions for sending emails without the need for complex server-side code. With its built-in editor and seamless integration with JavaScript, MailSlurp makes it easy to connect email providers, create templates, and send emails directly from your application.

Overall, JavaScript’s versatility makes it a valuable tool for email transmission, offering developers a range of options to suit their specific needs. Whether you’re looking to enhance user interactions or streamline your email sending process, JavaScript has you covered.