Need Help Making Sure You Have Only One SPF Record and That It Is Valid?
Our Tool Can Help!
Sending “authenticated” email these days is virtually required, but not every sender can do or does do DKIM signing just yet, so it’s important that your SPF record be correct.
It’s pretty straightforward (when you are ready) to get your DKIM and DMARC records published in public DNS, but publishing an SPF record correctly seems to be a common challenge for many senders.
Indeed, hardly a week goes by when a customer doesn’t reach out to say that one of their users doesn’t understand why Zimbra is marking an otherwise trusted third-party sender’s email as Spam — only to find out the third-party sender’s domain has a defective SPF record.
So we created a bash script we could run ourselves to test a sender’s SPF record and find the problems. Quite surprisingly, many senders had two or more SPF records (a big no-no!), so email delivery was dependent on which one was selected during a DNS lookup.
None of the many SPF record checkers out there that we could find tested for multiple SPF records, and many (like Mimecast) annoyingly require you to register to get the results of their test.
The bash script we created works great, so we felt it might be nice to share it publicly, after porting it as a WordPress plugin.
Are you or your customers having email deliverability issues you suspect are SPF-related?
You can use our tool to analyze a domain’s SPF record and verify RFC 7208 compliance.
Please do note that the tool is Copyright 2025 Mission Critical Email LLC, with all rights reserved, and that the tool is provided strictly as-is and without warranty of any kind!
Hope that helps!
Mark