Email deliverability guides: SPF, DKIM, DMARC

Plain-English guides to email authentication and deliverability: SPF, DKIM, DMARC, and why your email lands in spam.

How to Check If My Domain Is Blacklisted Check if your domain is blacklisted, test SPF, DKIM, DMARC, MX, and find the DNS, IP, reputation, or sender issues that push email to spam or rejection.
How to set up DMARC without breaking your email A step-by-step guide to setting up DMARC the safe way: start at p=none to monitor, then move to quarantine and reject once your mail is passing. No jargon.
SPF, DKIM, and DMARC Explained SPF, DKIM, and DMARC explained in plain English: what each record does, how alignment works, and how to fix the issues that send business mail to spam.
What Is DKIM and How Does It Work? Learn what DKIM is, how selectors, signatures, SPF, and DMARC work together, and how to check your domain before Gmail or Outlook routes mail to spam.
Why is my email going to spam? The fixes that actually work If your email keeps landing in spam, the cause is almost always email authentication: SPF, DKIM, or DMARC. Here is how to find which one is broken and fix it.

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