JavaScript Program to Validate An Email Address

Example: Using Regex

// program to validate an email address

function validateEmail(email_id) {
    const regex_pattern =      /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
    
    if (regex_pattern.test(email_id)) {
        console.log('The email address is valid');
    }
    else {
        console.log('The email address is not valid');
    }
}

validateEmail('abc123@gmail.com');
validateEmail('hello@com');

Output

The email address is valid
The email address is not valid

In the above program, the regular expression pattern

/^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/

checks if an email address is valid or not.

The test() method returns true if there is a match in the string with the regex pattern.

The regular expression (regex) describes a sequence of characters used for defining a search pattern.