How Email Delivery Works: SMTP, MX Records, and Webhooks Explained

A behind-the-scenes look at how email travels from sender servers through MX records and SMTP daemons into disposable browser mailboxes.

Infrastructure Engineering

How Email Delivery Works: SMTP, MX Records, and Webhooks Explained

The Life Cycle of an Email Message

When an email is dispatched, the sender's Mail Transfer Agent (MTA) queries the Domain Name System (DNS) for the recipient domain's Mail Exchanger (MX) records. Once located, an SMTP handshake occurs over port 25 or 587.

From SMTP to Browser in Milliseconds

TempMail connects high-speed cloud mail routers with webhook ingestion endpoints. As soon as an inbound email arrives, the payload is parsed, validated, safely sanitized, and indexed into storage, immediately appearing on the user's active browser session via automatic polling.

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