How does an email verifier check if an address is real?
The verifier runs a multi-step process: it validates the syntax against RFC 5322 rules, looks up the domain's MX records to confirm a mail server exists, then opens an SMTP connection to ask the server whether it will accept mail for that address — all without actually sending an email. It also checks against known disposable domain lists and identifies role-based addresses like info@ or admin@.
What is a catch-all email address and why does it matter?
A catch-all domain accepts email sent to any address at that domain, whether or not a mailbox exists. SMTP verification will return “deliverable” for every address. Catch-all detection flags these domains so you know the result is inconclusive and the address may still bounce.
Is it safe to verify email addresses? Will the recipient know?
Yes, verification is safe. The tool connects to the recipient's mail server and issues an SMTP handshake but never sends an actual email. The recipient will not receive any message or notification.
