The vocabulary of deliverability — hard bounces, catch-all domains, spam traps, SMTP, SPF/DKIM/DMARC — defined clearly, with no jargon left unexplained.
The percentage of sent emails that could not be delivered and were returned by the receiving server.
Read definitionA mail server configured to accept email for every possible address at a domain, even ones that do not exist.
Read definitionThe percentage of recipients who mark your email as spam, a key signal mailbox providers use to judge senders.
Read definitionA short-lived email address from a temporary-mail service, used to avoid giving out a real address.
Read definitionAn email-authentication standard that adds a cryptographic signature proving a message was not altered in transit.
Read definitionA policy standard that builds on SPF and DKIM to tell receivers what to do with mail that fails authentication.
Read definitionA published list of IP addresses or domains known for sending spam, used by mail servers to block or filter senders.
Read definitionThe ability of your email to actually reach recipients' inboxes rather than being blocked or filtered to spam.
Read definitionThe process of checking whether an email address is real, correctly formatted, and able to receive mail before you send to it.
Read definitionAn anti-spam technique where a server temporarily rejects mail from unknown senders, expecting legitimate ones to retry.
Read definitionA permanent delivery failure that happens when an email is sent to an address that does not exist or cannot receive mail.
Read definitionThe ongoing practice of keeping an email list free of invalid, risky, and unengaged addresses.
Read definitionA DNS record that tells other servers which mail server is responsible for receiving email for a domain.
Read definitionAn address tied to a job function or team rather than a person, such as info@, support@, or sales@.
Read definitionA trust score that mailbox providers assign to your sending IP and domain, which determines whether your mail reaches the inbox.
Read definitionThe standard protocol mail servers use to send and receive email across the internet.
Read definitionChecking whether a specific mailbox exists by starting an SMTP conversation with the receiving server without sending a real email.
Read definitionA temporary delivery failure caused by a transient issue, such as a full mailbox or a server that is briefly unavailable.
Read definitionAn email address used by mailbox providers and blocklists to identify senders with poor list hygiene.
Read definitionAn email-authentication standard that lets a domain list which servers are allowed to send mail on its behalf.
Read definitionThe most basic email check: confirming an address is correctly formatted before any network lookups.
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