Email Verification Glossary
Everything you need to know about email verification, deliverability, and infrastructure — explained in plain language.
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DKIM (DomainKeys Identified Mail)
A cryptographic email authentication method that verifies an email was sent by an authorized server and wasn't altered in transit.
DMARC (Domain-based Message Authentication)
A protocol that tells receiving servers what to do when SPF or DKIM checks fail for your domain.
Disposable Email
A temporary email address created for one-time use, often to avoid giving out a real email address.
DNS TXT Record
A type of DNS record used to store text-based data, commonly used for email authentication (SPF, DKIM, DMARC).
Double Opt-In
A two-step email subscription process where the user must confirm their signup by clicking a link in a verification email.
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Email Verification
The process of confirming whether an email address is valid, deliverable, and belongs to a real person.
Email Blacklist (RBL)
A database of IP addresses and domains known to send spam, used by ISPs to filter incoming email.
Email Warm-Up
The process of gradually increasing email send volume on a new IP address or domain to build trust with ISPs.
Email Authentication
The umbrella term for protocols (SPF, DKIM, DMARC) that verify a sender's identity and prevent email spoofing.
Engagement Rate
The percentage of email recipients who interact with your emails through opens, clicks, replies, or forwards.
Email Hygiene
The set of practices used to maintain a clean, healthy email list by removing invalid, inactive, and risky addresses.
Email Append
The practice of adding email addresses to existing customer or contact records using third-party data sources.
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IP Reputation
A trust score assigned by ISPs to a specific sending IP address based on its email sending history and behavior.
Inbox Placement Rate
The percentage of sent emails that successfully land in the recipient's primary inbox rather than spam, promotions, or junk folders.
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Soft Bounce
A temporary email delivery failure that may succeed on retry.
Sender Reputation
A score assigned by ISPs to your email sending domain/IP that determines whether your emails reach the inbox.
SPF (Sender Policy Framework)
A DNS record that specifies which mail servers are authorized to send email on behalf of your domain.
SMTP Handshake
The process of connecting to a mail server to verify if a specific mailbox exists, without actually sending an email.
Spam Score
A numerical rating that predicts how likely an email is to be classified as spam by ISP filters.
Go deeper with our blog
In-depth guides on email verification, deliverability, and list hygiene.