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Email Security Made Easy: SPF, DKIM, DMARC & BIMI

When you send email from your domain, you want it to be trusted and not go to spam. Four tools help make that happen: SPF, DKIM, DMARC, and BIMI. Let’s explain each one in plain English, and how to set them up. 1. SPF – Who’s Allowed to Send Emails for You What It Does: SPF is like a guest list. It tells the internet which servers are allowed to send emails from your domain. How to Set It Up: Add a TXT record to your domain’s DNS that looks like this:
This tells the world that mySMTP.com is allowed to send emails for you. How to Check It Works: Go to test.smtp.ai, send a test email, and look for “SPF Pass”. 2. DKIM – Proves the Email Is Really From You What It Does: DKIM puts a digital “signature” on your emails, so others know they haven’t been changed. How to Set It Up:
  • mySMTP gives you a DKIM record.
  • You add this TXT record to your domain’s DNS.
Example:
How to Check It Works: Use test.smtp.ai again and check for “DKIM Pass.” 3. DMARC – Tells Email Servers What to Do if SPF/DKIM Fail What It Does: DMARC is like a security rule. It tells email services what to do if someone tries to send fake email from your domain. How to Set It Up: Add a TXT record to your DNS like this:
  • p=none means “just watch, don’t block yet.”
  • rua= is where reports are sent.
How to Check It Works: Run a test at test.smtp.ai and look for “DMARC Pass.” 4. BIMI – Show Your Logo in Inboxes What It Does: BIMI shows your brand logo next to your emails in some email apps (like Gmail). How to Set It Up:
  • You must already have DMARC working.
  • Upload your logo (in SVG format).
  • Add a TXT record like this:
(You may need a special certificate called a VMC.) How to Check It Works: Use test.smtp.ai, but note: BIMI isn’t supported everywhere yet. Final Tips
  • Double-check your DNS settings.
  • Test with test.smtp.ai.
  • Watch for reports if anything goes wrong.
  • All this helps your emails land in inboxes — and look more professional!