Regex Tester & Validator

This regular expression validates email addresses by enforcing strict character rules for the local part, allowing alphanumeric characters alongside specific symbols like -, #, $, %, ', and _. It validates the domain to ensure it contains one or more alphanumeric subdomains separated by dots. Additionally, it uses a negative lookahead to guarantee the top-level domain is not entirely numeric, making it suitable for robust client-side email validation.