Email Deliverability Concepts

Authoritative definitions and explanations for key email deliverability concepts used throughout InboxAlly documentation.

16 articles

Email Deliverability

Email deliverability is the ability of an email to reach the recipient's inbox rather than being filtered to spam, bounced, or blocked.

Updated March 10, 2026

Inbox Placement

Inbox placement is the percentage of sent emails that successfully land in the recipient's primary inbox rather than spam, promotions, or other folders.

Updated March 9, 2026

Seed Emails

Seed emails are real email addresses used to test and improve inbox placement by generating authentic engagement signals with mailbox providers.

Updated March 9, 2026

Engagement Signals

Engagement signals are recipient interactions — opens, clicks, replies, and reading time — that mailbox providers use to evaluate sender quality.

Updated March 10, 2026

Sender Reputation

Sender reputation is the score mailbox providers assign to email senders based on engagement, complaint rates, and sending behavior.

Updated March 10, 2026

Spam Filters

Spam filters are automated systems used by mailbox providers to evaluate incoming emails and determine whether they should reach the inbox or be blocked.

Updated March 10, 2026

Mailbox Providers

Mailbox providers are services like Gmail, Yahoo, and Microsoft Outlook that host email accounts and make inbox placement decisions for their users.

Updated March 9, 2026

Spam Complaints

Spam complaints occur when email recipients mark a message as spam, directly damaging the sender's reputation with mailbox providers.

Updated March 9, 2026

Open Rate

Open rate is the percentage of delivered emails that recipients open, serving as a key engagement metric and deliverability signal.

Updated March 9, 2026

Engagement Rate

Engagement rate is the overall measure of how actively recipients interact with your emails, combining opens, clicks, replies, and other interactions.

Updated March 9, 2026

Email Authentication

Email authentication is the set of protocols — SPF, DKIM, and DMARC — that verify a sender's identity and protect against spoofing.

Updated March 10, 2026

Reputation Recovery

Reputation recovery is the process of rebuilding sender reputation after a deliverability setback such as blocklisting, high complaint rates, or spam folder placement.

Updated March 10, 2026

Spam Folder Placement

Spam folder placement occurs when mailbox providers route an email to the recipient's spam or junk folder instead of the inbox.

Updated March 10, 2026

Email Warmup

Email warmup is the process of gradually increasing sending volume on a new or dormant email domain or IP to establish sender reputation with mailbox providers.

Updated March 10, 2026

List Hygiene

List hygiene is the practice of regularly cleaning and maintaining email lists to remove invalid, inactive, and risky addresses that damage sender reputation.

Updated March 10, 2026

Spam Traps

Spam traps are email addresses used by mailbox providers and blocklist operators to identify senders with poor list practices.

Updated March 10, 2026