6 articles
Greylisting causes false "unknown" results in email verification. See how it works and how SendSure resolves it automatically.
How to evaluate, choose, and integrate an email verification API — with code examples in Node.js, Python, and cURL.
The complete guide to email syntax validation — RFC rules, regex patterns, common mistakes, and why syntax checking alone isn't enough.
A deep-dive into the SMTP handshake protocol — how email verifiers talk to mail servers to check if an address exists.
From regex to SMTP handshakes — the 5 proven methods to validate email addresses, with code examples and accuracy comparisons.
Real-time API verification for signups vs. bulk list cleaning — when to use each approach and how to combine them.
A weekly breakdown of what's landing in inboxes — and what isn't.
