DKIM: The Secret to Improved Email Deliverability

The secret to improved email deliverability isn’t in your email server. It’s actually in your DNS server. That’s because the DNS server record is where you’ll publish a cryptographic public key as a specially-formatted TXT record. And that cryptographic key is the crucial element in email deliverability because it supports email delivery with DKIM.

DKIM enables you to send authenticated emails, and authenticated emails look less like spam and are therefore more likely to make it into the inboxes.

When a mail message is sent by an outbound mail server, the server generates and attaches a unique DKIM signature header to the message. This header includes two cryptographic hashes, one of specified headers, and one of the message body (or part of it). The header contains information about how the signature was generated.

When an inbound mail server receives an incoming email, it looks up the sender’s public DKIM key in DNS. The inbound server uses this key to decrypt the signature and compare it against a freshly computed version. If the two values match, the message can be proved to be authentic and unaltered in transit.

DKIM is the secret to improved email deliverability because it’s designed to detect forged sender addresses in emails. Consequently, DKIM signing improves the inbox placement of mailbox providers like Gmail and Office365.

High Deliverability

If you want to ensure high deliverability rates of your high volume emails, you’re going to need correctly configured DKIM signatures in your outbound emails. And if you’re not sure how to do it, then you need to find an outbound SMTP service provider who does know.

In addition to correctly formatted DKIM signed emails, a quality outbound SMTP provider also offers correctly configured SPF and DMARC records. They optimize your sending routes and closely monitor your IP reputation to ensure you the best possible delivery rates. A zero spam policy allows blocking or restricting messages that would damage reputation.

When you want to ensure your emails get delivered, look for an outbound SMTP service that sets up in minutes and comes with live 24/7 technical support.