Free tools to check and fix your email setup.

A checker reads what you've published and tells you whether it's correct. That's genuinely valuable: most deliverability problems start with a record that's missing, malformed, or stuck in a half-deployed state, and a thirty-second lookup catches those before they cost you a campaign. Since Gmail, Yahoo, and Microsoft turned authentication from best practice into a hard requirement, a clean SPF, DKIM, and DMARC setup is the price of admission to the inbox — and a checker confirms you've paid it.

What a checker can't do is tell you whether every real message passes. A record can be flawless while a forgotten sending source quietly fails authentication, because the gap lives in the mail, not the DNS. That's the boundary between checking and verifying, and it's why these tools each point to the next step: the live message test, the aggregate reports, and ultimately the ongoing operation of keeping every source aligned as you add tools and subdomains. The tools find the problem; keeping it fixed is what we do.