Question 1

What does this DKIM checker validate?

Accepted Answer

This DKIM checker and DKIM lookup tool resolves selector records, shows the queried DNS name, returns the live TXT value when found, and highlights warnings around selector choice, key length, or record validity.

Question 2

Can I run a DKIM lookup without a selector?

Accepted Answer

Yes. If you do not provide a selector, the tool checks common selector names and shows the names it tried. That is useful when you inherit a sender domain and do not yet know the active selector.

Question 3

Why does key length matter in DKIM?

Accepted Answer

Key length affects signing strength and trust posture. Teams usually want to know whether the selector is using an expected modern key size before relying on it in production.

Question 4

How should I use the result?

Accepted Answer

Use the lookup result with SPF and DMARC checks, then confirm real messages show the expected selector and a passing DKIM verdict in Authentication-Results.

Free DKIM checker and DKIM lookup tool

Check the live DKIM selector for a domain