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#SMTP relay

5 articles tagged with SMTP relay.

Email API vs SMTP: Which to Use When
Transactional & SMTP

Email API vs SMTP: Which to Use When

An email API POSTs JSON over HTTPS; SMTP relay runs a multi-step protocol conversation on port 587. This guide compares the two on latency, batching, error handling, templates, and vendor lock-in, includes a full port reference table, and shows the hybrid setup most teams actually end up running.

Aug 18, 20269 min read
Best Email APIs Compared (2026)
Transactional & SMTP

Best Email APIs Compared (2026)

How to choose the best email API in 2026 without getting lost in feature checklists. Covers the eight evaluation criteria that actually predict deliverability, the four categories providers fall into and their tradeoffs, how to read API docs like an engineer, a REST-versus-SMTP comparison table, and a safe migration sequence.

Aug 14, 20269 min read
What Is a Transactional Email? (+ Examples)
Transactional & SMTP

What Is a Transactional Email? (+ Examples)

A transactional email is a one-to-one message triggered by a user action. Here is how it differs from marketing email, 16 examples to audit your product against, the SMTP ports and DNS records you need, and where promotional content crosses the line.

Aug 13, 20268 min read
What Is an SMTP Relay (and When to Use One)?
Transactional & SMTP

What Is an SMTP Relay (and When to Use One)?

An SMTP relay forwards your outgoing email through trusted servers so it reaches the inbox. Learn how relays work, how they differ from direct delivery, and when to use one.

Jul 11, 20268 min read
SMTP Relay Services: How They Work + What to Look For
Transactional & SMTP

SMTP Relay Services: How They Work + What to Look For

How SMTP relay services deliver your email, and the concrete criteria to evaluate one: authentication, IP reputation, own-domain sending, reporting, and pricing.

Jul 10, 20269 min read