Also known as: Email Validation
The process of checking whether an email address is real, correctly formatted, and able to receive mail before you send to it.
Email verification (often used interchangeably with email validation) is the set of checks that determine whether an address is safe to send to. A thorough verifier works in layers: it confirms the syntax is valid, looks up the domain's MX records to confirm the domain can receive mail, and then probes the mailbox itself over SMTP to confirm the specific address exists.
Good verification goes further than "does it exist." It also flags disposable addresses, role accounts, and catch-all domains — addresses that may technically accept mail but carry real deliverability risk. The output is usually a status (valid, invalid, risky, catch-all, unknown) plus a confidence score.
Verifying before you send protects your sender reputation: every message to a dead address is a hard bounce, and mailbox providers watch your bounce rate closely.
A DNS record that tells other servers which mail server is responsible for receiving email for a domain.
The standard protocol mail servers use to send and receive email across the internet.
A permanent delivery failure that happens when an email is sent to an address that does not exist or cannot receive mail.
A mail server configured to accept email for every possible address at a domain, even ones that do not exist.
See it in action
Check any address against BounceShift's multi-layer engine — syntax, MX, disposable, and role checks free, with full SMTP verification on signup.