
If you’re aware of how email can play a critical role in acquiring and retaining customers, then you’ve probably heard of SPF and DKIM.
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Understanding SPF and DKIM to Improve Email Deliverability
If you’re aware of how email can play a critical role in acquiring and retaining customers, then you’ve probably heard of SPF and DKIM. You might even know that SPF and DKIM are fundamental components of email authentication and help protect email senders and recipients from spam, spoofing, and phishing.
But what do these terms actually mean and how are they related to email deliverability? If you’re looking to better understand SPF and email DKIM, let’s start with some definitions.
Sender Policy Framework (SPF) Definition:
SPF is a form of email authentication that defines a process to validate an email message that has been sent from an authorized mail server in order to detect forgery and to prevent spam. The owner of a domain can identify exactly which mail servers they are able to send from with SPF protocols.
DomainKeys Identified Mail (DKIM) Definition:
DKIM is a form of email authentication that allows an organization to claim responsibility for a message in a way that can be validated by the recipient. DKIM uses “public key cryptography” to verify that an email message was sent from an authorized mail server, in order to detect forgery and to prevent delivery of harmful email like spam.
SPF and DKIM Explained Simply
The Importance of Authentication Alignment
Using the benefits of a third-party email service provider (ESP) is a wise investment that can still pose a challenge with domain alignment. In an aligned domain, your business appears as the sender even if your ESP is sending on your behalf. Your emails may still experience delivery even if your domain is out of alignment. An aligned domain passes through spam filters more easily to even further boost your inbox placement opportunities.

The Value of SPF and DKIM
If you are a business that sends commercial or transactional emails, it’s critical to use both SPF and DKIM. Not only will these protocols protect your business from phishing and spoofing attacks, but SPF and DKIM ultimately help protect your customer relationships and brand reputation. Bear in mind that these are just a few of the many steps you can take to ensure business-critical emails reach your customers’ inboxes on time and don’t end up in spam folders.
Summing Up
In a nutshell, SPF allows email senders to define which IP addresses are allowed to send mail for a particular domain. DKIM on the other hand, provides an encryption key and digital signature that verifies that an email message was not forged or altered.
Authentication itself is not a testimonial on the value of your content. Use proper email etiquette and best practices for inbox placement — spammy content will still generate complaints and unsubscribes even if authenticated.
When these email authentication methods are properly implemented, you will be one step closer to improving your email deliverability and sending secure emails that drive revenue for your business.