An email validation tool typically works in multiple stages:
Syntax Check: Validates the format of the email address. Domain Check: Ensures the domain is valid and has a mail server set up. MX Record Check: Verifies the email server's existence by checking its MX (Mail Exchange) records. SMTP Authentication: Connects to the mail server to confirm the recipient's email address exists. Catch-All Check: Determines if the domain is set to receive all emails sent to it, even if the specific address does not exist.