Announcing New Email Deliverability Lookups and Monitors

This week we released tools and monitors that test your servers for DKIM and DMARC standards compatibility.  These two standards help companies send and receive email more safely and should be used by any company running their own email servers to ensure email deliverability.

What are these standards?


DKIM, or DomainKeys Identified Mail, is a standard that allows an organization to cryptographically sign an email message in order to take responsibility for that message.  Receivers can then use this digital signature in their process for approving or rejecting the email in their spam filter.  As DKIM signatures are associated with a domain, the reputation of that domain is the basis for evaluation.


DMARC, or Domain-based Message Authentication, Reporting & Conformance, is a standard for how email receivers authenticate email messages using SPF and DKIM.  DMARC policies are published by senders via DNS.  These policies tell a receiver that the messages sent were protected by SPF and DKIM and how to respond to messages that did not pass the receivers filters, such as spam filters or virus filter.

Why do I need it?

Email is a generally insecure method of communication.  Spam and phishing attacks leverage email because it easy to spoof and highly trusted by naive consumers.  For example, many people trust an email simply because it contains a company’s logo and appears to come from that company’s email address, both of which are easy to fake.  Email service providers like Google (Gmail), Microsoft (Hotmail/, and Yahoo! value DKIM and DMARC because it simplifies their algorithms for filtering trusted email from spam and phishing attacks.  If you are a small business targeting business or consumer customers, you need to adopt DKIM and DMARC to ensure your emails get through to your customers.

How do I use MxToolbox?

Once you have DKIM and DMARC setup, you can use MxToolbox to check your configurations and ensure they are accessible to the outside world.  We even offer these as monitors which will alert you if DKIM or DMARC is unaccessible or changes.

DKIM lookup result for using their google key


Typical DMARC lookup results for

As with all our DNS monitor types, DKIM and DMARC monitors check your configuration every 5 minutes.