DKIM checker - check DKIM record

Use DKIM checker to check if a DKIM record on a domain.

To learn how to implement SPF/DKIM/DMARC, check out this definitive, step-by-step guide:
How to Implement SPF/DKIM/DMARC to Prevent Email Spoofing/Phishing

Enter domain to check DKIM record for, e.g., dmarcly.com
._domainkey
Do NOT enter ._domainkey as it is appended automatically
  Check DKIM Record

Found DKIM record in DNS:


Tags
Tag Value Explanation
v DKIM1 DKIM protocol version.
g * Some organizations assign specific business functions to discrete groups, inside or outside the organization. This key is to authorize that group to sign some mail, but to constrain what signatures they can generate. The DKIM granularity (the 'g=' tag) facilitate this kind of restricted authorization.
h Allowing all algorithms The 'h=' tag provide a list of mechanisms that can be used to produce a digest of message data. ('sha1' or 'sha256' can be used).
n Notes that might be of interest to a human.
s * The 's=' provides a list of service types to which this selector may apply. ('*' and 'email' are used most often)
q dns/txt The 'q=' tag provides for a list of query methods. ('dns' is used most often)
l 0 Body length limits (in the form of the 'l=' tag) are subject to several potential attacks.
k rsa The 'k=' tag provide a list of mechanisms that can be used to decode a DKIM signature. ('rsa' is used most often)
t s The 't=' tag provides a list of flags to modify interpretation of the selector. These DKIM Selector Flags for additional flags are optional. ('y' and 's' are often used)
p Base64 encoded public key.

Help on DKIM checker

The DKIM record checker, aka DKIM record validator, checks if a DKIM record is published at a selector on a domain, and if the DKIM record syntax is correct.

DKIM is an email security protocol which checks if an email has been tampered with in transit.

A DKIM selector is a string used to specify the location of the DKIM public key on a domain. The main purpose of selectors is to allow multiple DKIM keys under the same organization's domain name.

For example, you can choose a selector "march20" and create a DKIM public key at that selector on domain "example.com":
march20._domainkey.example.com.

You can also choose another selector "june22" and create a DKIM public key at that selector on domain "example.com":
june22._domainkey.example.com.

Note that the ._domainkey part in the above examples: it's required for DKIM to work.

A DKIM record is a TXT record published in the DNS. It consists of a list of tags, one of which is the "p=" tag, which contains the public DKIM key.

You can have as many as you want, as long as your DNS hosting service allows.

A DKIM public key is the value of the "p=" tag inside a DKIM record.