Super simple email validation with JavaScript

Question

I'm making a really simple email validation script that basically just checks the following

1. that the email isn't blank
2. the the email contains an @ symbol with at least 1 character before it
3. that there is a domain ie @ with at least 2 letters after it
4. that it ends with a fullstop with at least 2 letters after it

I know there are many more checks, but I look at these regex rules and my mind stops working. I figure if I started with something small like this I might be able to wrap my brain around more complex rules.

Currently using some jQuery I do the following:

 var booking_email = $('input[name=booking_email]').val();

 if(booking_email == '' || booking_email.indexOf('@') == -1 || booking_email.indexOf('.') == -1) {

   // perform my alert

 }

This is enough to stop 90% of bogus emails so far... I would just like to make it a bit more effective because currently my rule will allow emails like '@example.com' or 'user@domain.' because it only checks that there is a fullstop and an @ symbol.

Answer 1

What others have suggested should work fine, but if you want to keep things simple, try this:

var booking_email = $('input[name=booking_email]').val();

if( /(.+)@(.+){2,}\.(.+){2,}/.test(booking_email) ){
  // valid email
} else {
  // invalid email
}

Even if you decide to go with something more robust, it should help you understand how simple regex can be at times. :)

Answer 2

The least possible greedy validation you an do is with this RegExp /^\S+@\S+\.\S+$/

It will only ensure that the address fits within the most basic requirements you mentioned: a character before the @ and something before and after the dot in the domain part (\S means "anything but a space"). Validating more than that will probably be wrong (you always have the chance of blacklisting a valid email).

Use it like this:

function maybeValidEmail (email) { return /^\S+@\S+\.\S+$/.test(email); }

Answer 3

Try:

function valid_email(email) {
   return email.match(/^([\w\!\#$\%\&\'\*\+\-\/\=\?\^\`{\|\}\~]+\.)*[\w\!\#$\%\&\'\*\+\-\/\=\?\^\`{\|\}\~]+@((((([a-z0-9]{1}[a-z0-9\-]{0,62}[a-z0-9]{1})|[a-z])\.)+[a-z]{2,6})|(\d{1,3}\.){3}\d{1,3}(\:\d{1,5})?)$/i);
}

That is the best available email validation regex, according to this article. I recommend using this, unless your goal is something really simple but not fully compatible.

Answer 4

RegexLib.com ( http://regexlib.com/Search.aspx?k=email ) has hundreds of email validation routines for a reason. I'd recommend you read this article: http://www.unwrongest.com/blog/email-validation-regular-expressions/ and if you decide to continue using regex for validation, my favorite testing utility is the free regex designer available for free here: http://www.radsoftware.com.au/regexdesigner/ ... test all emails in a LARGE list (available for free download or purchase ... or use your own current DB) to ensure your regex is acceptable within your constraints.

I would recommend a basic test (many at the top of regexlib.com ... I'm not taking credit for the work of theirs I use routinely), followed by a email validation routine that requires user interaction. It is the only real way to 'validate' an email address.

Answer 5

Emails are very difficult to test, but you can have a somewhat restrictive, but simple email validation. I use this one myself, which does a pretty decent job of making sure it's 95% an email address.

var simpleValidEmail = function( email ) {
    return email.length < 256 && /^[^@]+@[^@]{2,}\.[^@]{2,}$/.test(email);
};

I would recommend this for a 'simple' validation.

To see why this is a hard thing to solve, see: How to validate an email address using a regular expression?

Update: corrected regular expression

Answer 6

You can try this:

var booking_email = $('input[name=booking_email]').val();
if(booking_email.match(/^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/)) {
  // valid email
} else {
  // not valid
}

Answer 7

Based on Ian Christian Myers reply before this, this answer adds + sign and extend to tld with more than 4 chars

function validateEmail(email) {
    const regex = /^[a-zA-Z0-9.+_-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,15}$/;
    return regex.test(email);
}

Answer 8

<input type="email" name="email" required>

This should work I guess.

type = email will check for basic validations and required will check if the field is blank.

Answer 9

If you want to check only for Business Emails then try this :

<script type="text/javascript">
$(document).ready(function(e){
     $('#sendReq').click(function(){ 
     var email = $('#emailAddress').val();
     var reg = /^([\w-\.]+@(?!gmail.com)(?!yahoo.com)(?!hotmail.com)(?!yahoo.co.in)(?!aol.com)(?!abc.com)(?!xyz.com)(?!pqr.com)(?!rediffmail.com)(?!live.com)(?!outlook.com)(?!me.com)(?!msn.com)(?!ymail.com)([\w-]+\.)+[\w-]{2,4})?$/;
      if (reg.test(email)){
     return 0;
     }
     else{
     alert('Please Enter Business Email Address');
     return false;
     }
     });
    });
</script>

Answer 10

The is-email package on npm is super simple, if a little loose, just:

var matcher = /^[a-zA-Z0-9.!#$%&'*+\/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$/;

function isEmail(string) {
  return matcher.test(string);
}

It was written by segment.io, who deal with a lot of emails.