Email Validation Technical

Learn the key differences between hard and soft bounces, how they affect deliverability, and how email validation helps prevent them.

Learn what an MX record check is, how it supports email validation, and why it matters for deliverability. Includes tools, use cases, and CLI tips for devs.

Learn how to get off an email blacklist, avoid spam traps, and recover deliverability with actionable steps. Includes blacklist check tools, trap prevention, and validator tips.

Learn what correct email syntax looks like with this RFC-compliant checklist. Includes regex tips, common pitfalls, and a downloadable PDF for your team.

Learn how to measure your email deliverability rate accurately. Follow this step-by-step guide to diagnose issues, improve inbox placement, and boost your ROI.

Confused about email authentication? Here's a no-fluff guide to setting up DKIM, SPF, and DMARC so your emails don't end up in spam.

Greylisting is a silent inbox killer. Learn how it works, how it affects your cold outreach, and how Lero detects it in real time.

Need to clean huge email lists fast? Discover how Lero validates 1M+ emails with sub-second response times—without sacrificing accuracy.

Email validation can run via API or bulk uploads—but which is right for your workflow? Here's a technical breakdown to help you decide.

What's a "normal" bounce rate in 2025? Here's the latest industry data, what it means, and how to keep yours below the danger zone.

Complete guide to understanding SMTP response codes, their meanings, and how to handle them effectively