What DKIM verifies
DKIM lets a mailbox provider verify that an email was authorized by the sending domain and was not materially changed in transit.
Free outbound tool
Free DKIM Checker
Check a DKIM selector and domain for a public key record and common DKIM setup issues.
live
DKIM checker
Selector and domain lookup that validates DKIM syntax and common provider selectors.
Selector
Try google, selector1, selector2, k1, default.
Record
Missing
No DKIM TXT for this selector.
DKIM TXT
0 recordsselector._domainkey.company.com
No record returned
What this tool should cover
A useful DKIM checker should cover selector lookup, how signatures work, what the checker verifies, default tags, and common fixes.
How selectors work
A selector points to a specific DKIM public key under selector._domainkey.yourdomain.com. Common selectors include google, selector1, selector2, k1, default, and provider-specific values.
Common DKIM failures
The most common failures are using the wrong selector, publishing the record at the wrong host, missing the p value, copied whitespace errors, and sending from a platform that is not aligned with the domain.
Frequently asked questions
What does DKIM stand for?
DKIM stands for DomainKeys Identified Mail.
Can I check DKIM without a selector?
Usually no. DKIM records are selector-specific, so you need the selector from your email provider or sending platform.
Where do I find my DKIM selector?
Look in your email provider's domain authentication settings. Google commonly uses google, while Microsoft and other providers often use selector1 and selector2.
Does DKIM replace SPF or DMARC?
No. DKIM, SPF, and DMARC work together. DKIM verifies signed mail, SPF authorizes sending servers, and DMARC defines alignment policy.
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