How to validate emails properly in your app (beyond regex)

Regex is not enough for email validation. A string can pass /^[^\s@]+@[^\s@]+\.[^\s@]+$/ and still be completely useless — the domain doesn't exist, the mailbox is gone, or it's a throwaway address that will never convert. Here's what proper email validation looks like, and how to add it to your app in minutes. The problem with regex-only validation // This passes regex: " user@thisdoesnotexist12345.com " // domain has no MX records " test@mailinator.com " // disposable, will never convert " admin@yourcompany.com " // role email, useless for marketing " user@gmial.com " // typo, user will never get your email All of these are "valid" by format. None of them are useful. What you actually need to check Format — RFC 5322 compliance MX records — does the domain have mail servers? SMTP — does the mailbox actually exist? Disposable detection — is it a throwaway domain? Role detection — is it admin@, info@, support@? Typo suggestion — did they mean gmail.com? Using Email Validator API I built