What is SPF? SPF explained in simple words.


SPF in is an “Authentication Mechanism”. It’s like an ID card that your email carries and shows the the bouncer at the ISP’s door

Have you seen emails go out in the sun and get totally tanned? Well, they should have used a sunscreen with a Sun Protection Factor of 30.  Whaaaa?

Ok. I am kidding. The SPF in your sunscreen has nothing to do with the SPF in email marketing. 🙂  In this post I hope to convey in very simple words, without getting into any jargon what SPF is about.

SPF in Email Marketing is an “Authentication Mechanism”. It’s like a badge that your email carries and produces when the bouncer at the ISP asks for it.

  1. Who wants this authentication? The ISP who is showing you the email, for example Yahoo is the ISP that checks the email before letting it into your Yahoo Mail inbox. (Substitute Yahoo for Gmail, Hotmail etc.)
  2. What is being authenticated? The email is being checked to see if it was sent by a spammer.
  3. Who authorizes, or establishes if the email is genuine? Your website.

Here is how this happens:

  1. The ISP asks the email for its “ID” card or badge before letting the email in.
  2. The email then shows its “SPF” which is like its badge showing which website it has come from.
  3. The ISP then goes sneaking to the website, asking if the ID is genuine. The website looks at the badge and says “Yup. That’s my email, alright. Please let him pass.”

Here is this exchange in the format the “Internets” understand well, via stick people (who else?)!

SPF explained in simple wordsSPF explained in simple words

So you see the final authority in making sure that your emails land in the inbox is with your website. Your website needs to “authenticate” the email. The full form of SPF is Sender Policy Framework (seriously, I think the Internet people who come up with such names should go out in the sun more often!). If you don’t have SPF, you don’t get in the inbox. Simple.  Just like you should not go out in the sun without sunscreen don’t start your email marketing without SPF.

How is the SPF thingy done?  That’s for next post. In that post I will share the SPF details in slightly more technical terms.