Python program to validate email id

Here is a Python program that validates an email ID using a regular expression:

import re

def validate_email(email):
    pattern = r"^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$"
    if re.match(pattern, email):
        return True
    return False

# Test the function
email = input("Enter an email ID: ")
if validate_email(email):
    print("Valid email ID")
else:
    print("Invalid email ID")

Here's an explanation of the regular expression used:

• ^ matches the start of the string
• [a-zA-Z0-9._%+-]+ matches one or more of the following characters: letters (both uppercase and lowercase), numbers, dot (.), hyphen (-), underscore (_), percent (%), plus sign (+)
• @ matches the @ symbol
• [a-zA-Z0-9.-]+ matches one or more of the following characters: letters (both uppercase and lowercase), numbers, dot (.), hyphen (-)
• \. matches a period (.) character
• [a-zA-Z]{2,} matches the domain extension (it must be at least 2 characters long)
• $ matches the end of the string

You can modify this regular expression to fit your specific requirements.

Alternatively, you can use the email module in Python, which provides a more comprehensive way of validating email addresses:

import email.utils

def validate_email(email):
    try:
        email.utils.parseaddr(email)
        return True
    except email.utils.ParseError:
        return False

# Test the function
email = input("Enter an email ID: ")
if validate_email(email):
    print("Valid email ID")
else:
    print("Invalid email ID")

This function uses the email.utils.parseaddr function to parse the email address and check if it is valid. If the parsing fails, it returns False.