Terms below appear throughout guides on lead email verification. Each definition is one or two sentences; follow the links in the sidebar for the full guides.
Core terms#
Lead email verification
Lead verification confirms that a prospect's address exists and accepts mail before it enters a sequence, using syntax checks, MX lookups, SMTP probing, and catch-all detection. Enrichment adds firmographic and role data used for personalization.
SPF
A DNS record listing servers authorized to send for a domain. Checked against the connecting IP.
DKIM
A cryptographic signature on each message, verified with a public key in DNS.
DMARC
A policy record telling receivers what to do when SPF and DKIM fail alignment, plus reporting.
Alignment
Agreement between the visible From domain and the domain that passed SPF or DKIM.
Sender reputation
A provider's running assessment of a domain or IP based on complaints, bounces, engagement, and authentication.
Inbox placement
Share of accepted mail that lands in the inbox rather than spam.
Spam trap
An address that never opted in, used to catch senders with poor list practices.
BIMI
A DNS record pointing to a brand logo displayed next to authenticated mail; requires DMARC enforcement.
Feedback loop
A provider program that reports recipient spam complaints back to the sender.
Frequently asked questions#
What bounce rate is safe for cold email?
Under 2 percent. Above 5 percent, pause and re-verify the list before continuing.