How To Do Email Validation In JavaScript? [With Examples]

JavaScript is a programming language designed to create applications. It is much faster than other languages because it is so lightweight and easy-to-use. It is used for creating well-designed applications.

Email validation in JavaScript is important for the user experience of creating web applications. Validation helps in passing valid information to a server from the client of the web application.

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What is Validation?

Validation refers to the process of examining the values that the user inputs. It plays a crucial role in creating applications and enhances the user experience. Many fields, such as mobile numbers, emails, dates, and passwords, are validated through this process. 

JavaScript makes the validation process faster due to its faster processing of data than other server-side validation. Now let’s have a look at the implementation of the email validation in JavaScript.

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Email Validation in JavaScript

Email validation is one of the vital parts of authenticating an HTML form. Email is a subset or a string of ASCII characters, divided into two parts using @ symbol. Its first part consists of private information, and the second one contains the domain name in which an email gets registered.

Here are the ASCII characters of the first part:

  • Special characters such as # * + & ’ ! % @ ? { ^ } ”
  • Numeric characters (0 to 9)
  • Full stop, dot, etc., having a condition that it can’t be the email’s last or the very first letter and can’t be repeated after another.
  • Uppercase alphabets (A to Z) and Lowercase (a to z) alphabets

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The second part includes the following:

  • Dots
  • Digits
  • Hyphens
  • Letters

Using regular expressions is one of the best ways of email validation in JavaScript. It utilizes regular expressions for defining the character’s pattern.

Some of the examples of valid email id:


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Some Other Examples of Invalid Email Id

  • (one on another dots are not allowed)
  • Inownzsite()& (only characters, dash, underscore, and digits are allowed in the regular expression.)
  • (here @ symbol is not there)
  • (Here top-level domain can’t begin with a dot)
  • (here it can’t start with @ symbol)
  • Younourmetd345@abcd.b (“.b” is not a valid top-level domain)email.js

The file consists of a JavaScript code required for email validation. Here the regular expressions are used to validate an email at the client-side of an application.

Checkpoints for efficient email validation in JavaScript code:

  • Describe a regular expression to validate an email address
  • If an input value matches regular expressions
  • If it matches, sends the alert saying “email address is valid.”
  • If it does not match, send the alert saying, “email address is invalid.”

Related: Password Validation in Javascript

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Benefits of Email Validation in JavaScript

The process of email validation in JavaScript helps in improving data quality and marketing campaign performance. Your email campaigns will become better through validation in the following ways:

  • Eliminates Addresses that Degrade the Email List

With email validation in JavaScript, you will be able to stop bad and invalid email addresses significantly. This will provide you with a clean list of email contacts. So, it means a low risk of ending up in the spam section or getting blacklisted.

Remember that even a few bad email addresses can bring down the deliverability of your campaign. Proper email validation in JavaScript will help you run campaigns with accurate data.  

  • Lower Your Bounce Rate

You will get to know about the incorrect and undeliverable addresses through email validation in JavaScript. This knowledge will ensure that you can remove addresses from your mailing list that no longer come with the guarantee of a secure delivery. If you get rid of these addresses, you will notice a reduction in bounce rates. A clean mailing list can lower your bounce rates to a huge extent.

  • Save the Reputation of the Sender

While sending emails, you will end up creating a reputation among receivers. This sender’s reputation depends on various factors like bounce rates. It will also depend on how often receivers flag your emails as spam. 

Proper email validation in JavaScript will ensure that you are working with a verified list. So, you are less likely to become spam. Moreover, you will end up sending emails to addresses that won’t reject your messages and increase your bounce rates. This positive reputation among email receivers is quite beneficial for businesses. 

  • Gets Rid of Deliverability Issues

You need to take care of your deliverability issues as fast as possible. It will ensure that internet service providers are not counting you as a spammer. This increases the chance of emails ending up in the spam section. Even your targeted recipients will receive the emails in their spam folders. 

You will be able to easily solve the issue of deliverability with email validation in JavaScript. Proper validation reduces bounce rates to enhance the reputation of senders. It will help you win the trust of internet service providers and enjoy better deliverability. 

  • Lowers the Chance of Getting Blacklisted

Your domain or IP address can be blacklisted if your engagement is very low. The risk of getting blacklisted is also high when your email list contains expired or invalid addresses. In that case, your emails will go to the spam section. 

For example, the chances of your account being blacklisted increases if you get a lot of hard bounces or fall into a spam trap. You can mitigate these risks through proper email validation in JavaScript.

  • Prevents Resource Wastage on Invalid Leads

Your ESPs will offer plans with prices based on the number of members in your mailing list. If you have too many invalid addresses in your list, you will end up paying a large subscription fee. But a clean list through email validation in JavaScript will help you avoid hefty subscription fees. 

  • Increase the ROI of Your Email Campaign

You will be sending a few emails when you have a clean and valid list. Moreover, you will be able to send out even more targeted emails. By sending out targeted emails, you will be able to enhance the chance of user engagement. If your emails are capturing the attention of receivers, they are more likely to purchase from you. 

So, email validation in JavaScript will help you use your campaign resources more efficiently. You will be able to generate a higher revenue from lower expenses. It will enhance your return on investment for every dollar you invest. Therefore, you should become familiar with email validation in JavaScript and use it effectively. 

Validation Vs. Verification of Emails

It’s quite easy to confuse simple email validation in javascript . Both these methods ensure the integrity and quality of your email lists. But email validation and email verification are two different processes.

Email validation consists of checking email syntax and email address format. It also involves checking the email address structure to ensure that it is formatted correctly and follows standard rules. The main goal is to find spelling mistakes or formatting errors that can “invalidate” an email address.

But js code for email validation verification goes beyond syntax and format checks. This includes a more in-depth validation process to determine the deliverability of the email address. This includes checking DNS records and SMTP handshakes.

The process also checks how to send email without actually sending it. The goal is to ensure that the email address format can receive messages.

Email Validation Email Verification
This process evaluates the format and syntax of the email address. This process checks whether a particular email address exists.
Javascript email validation will help you maintain a clean email list without typos. Email verification will help in creating a high-quality email list. Therefore, this process is useful for enhancing deliverability.
This process is less accurate in determining whether an email address is real or active. This process is highly accurate in determining whether an email address is real or active.
It involves simple methods like regex and syntax check. It involves complex techniques like SMTP verification and DNS lookup.

Method of Email Validation in JavaScript

You will come across multiple methods for email validation in Javascript. Every method for email validation comes with its own pros and cons. Let’s learn about the most common methods:

  • Regular Expressions

Regular expressions are extremely valuable for pattern matching in JavaScript. They are useful for matching and finding particular patterns from different text formats, including email addresses. Writing regular expressions and maintaining them can be quite challenging. Moreover, these expressions for email validation in JavaScript can come with false negatives and positives.

  • Third-Party Libraries

If you need a comprehensive approach toward email validation in JavaScript, you will have to focus on third-party libraries. These libraries will try to figure out common spelling errors and provide recommendations for corrections. They will also help minimize the risk of errors. As a result, your validation will become much more accurate.

  • HTML5 Input Type

The HTML5 input type offers a seamless way of email validation in JavaScript. It is useful for validating email addresses in HTML forms. But this type of email validation is not supported on all browsers. Moreover, this method is not as accurate as using regular expressions or third-party libraries.

How to Implement Email Validation in JavaScript

The process to implement email validation in JavaScript is not very complicated. You can definitely write your own validation function. But you can also use a pre-existing library for email validation. Let’s learn a little more about the two methods of implementation:

  • Writing Your Own Email Validation Function

If you are writing your own email validation javascript function, regular expressions are necessary. You can also use other pattern-matching tools to determine the accuracy of email addresses and find errors.

  • Leveraging a Pre-Existing Library

If you want to use a pre-existing library, consider options like Validator.js or Mailcheck. You will have to include the pre-built library in your project. After the user submits the form, call the email validation javascript or regular expression for email validation in javascript function.

Email Validation Code in JavaScript

Given below is the email validation code in JavaScript. This code can validate if the email created or entered by the user is valid or not. Save the file as filename.js. 

// Code Snippet

function EmailValidation(enteredEmail)


var mail_format = /^w+([.-]?w+)*@w+([.-]?w+)*(.w{2,3})+$/;



alert(“Yeah! a valid email!”);


return true;




alert(“Sorry! an invalid email!”);


return false;



The JavaScript function is used in the HTML form as below. Save the file as filename.html:

<!DOCTYPE html>

<html lang=”en”>


<meta charset=”utf-8″>

<title>email validation in JavaScript</title>

<link rel=’stylesheet’ href=’form-style.css’ type=’text/css’ />


<body onload=’document.form1.text1.focus()’>

<div class=”mail”>

<h2>Enter the email for Validation</h2>

<form name=”form1″ action=”#”>


<li><input type=’text’ name=’text1’/></li>

<li> </li>

<li class=”Validate”><input type=”submit” name=”Validate” value=”Validate” onclick=”ValidateEmail(document.form1.text1)”/></li>

<li> </li>




<script src=”filename.js”></script>



The following code can add style to the form using CSS. Save the file as filename.css.

li {list-style-type: none;

font-size: 16pt;


.mail {

margin: auto;

padding-top: 20px;

padding-bottom: 20px;

width: 850px;

background : rgb(150, 195, 208);

border: 1px soild rgb(1, 20, 24);


.mail h2 {

margin-left: 36px;


input {

font-size: 28pt;


input:focus, textarea:focus{

background-color: white;


input submit {

font-size: 18pt;


Now you can execute the HTML code and get the email validation in JavaScript done.

Read: Javascript Projects in GitHub

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Email validation is very crucial to avoid making invalid email addresses. In this article, it is explained, with the code, to validate whether an email id is valid or not and let the system check and notify the user if the email id entered is not valid. 

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What is regular expression in programming?

Regular expressions are a type of pattern used to find and manipulate text. They are a commonly used tool for extracting data from strings or text. You can think of them being similar to wildcard characters such as star * or question mark ?. They are not just used in programming though. For example, the Linux command line uses regular expressions to search for files. Simply put, regular expression is a set of symbols and characters that can be used to match a certain pattern. It is used to match the pattern against a certain text. Using regular expression is one of the most powerful features in programming.

What are the applications of regular expressions?

Regular expressions are used in many places, but the most obvious one is text processing. If you have to parse a text file, search a string with hundreds of words in it, or validate an email-addresses, you use regular expressions. Like any specialized language, regular expressions can be a bit arcane, but if you take the time to learn them well, you’ll find them quite useful. The next thing is that you should learn to use a couple of regular expressions library like PCRE or JGsoft.

What are the applications of Javascript?

Javascript is the most prevalent language for web development and also one of the most popular programming languages. The applications of Javascript range from beginner to expert and covers foundation to advanced concepts which include calendars and date arithmetic, message boxes, image maps, image processing, video and audio players and more. Javascript is a scripting language that is used for adding dynamic and interactive content to Web pages. It's a lightweight programming language that is used by developers to make websites more interactive and appealing.

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