FairSoftware

Free tool

Free DKIM Record Checker

Look up a DKIM public-key record at selector._domainkey.<domain>.

About this tool

A free DKIM record checker. Enter your domain and selector — we query selector._domainkey.<domain> for its TXT record, then parse the DKIM fields (v, k, p, t) and estimate the RSA key length. Perfect for confirming a new DKIM setup or troubleshooting an existing signer.

How to use the Free DKIM Record Checker

  1. Enter your domain and the DKIM selector your provider uses (often 'default', 'google', 'selector1' or 's1').
  2. Click Check DKIM.
  3. The full record and parsed fields appear — copy the public key or verify it matches what your provider expects.

Frequently asked questions

How do I find my DKIM selector?
Look at the DKIM-Signature header in a message you sent — it contains s=<selector>. Providers often use google, selector1, mxvault, k1 or your own custom name.
What if the record isn't found?
Either the selector is wrong or DKIM isn't published for that selector. Double-check the DNS host is selector._domainkey.<domain> and that the record has propagated.
How long should the DKIM key be?
2048-bit RSA is today's standard. 1024-bit still works but is considered weak; some receivers already reject 512-bit as too short.
What does an empty p= mean?
An empty public key means the key has been revoked. Signatures using this selector will fail verification.

Related free tools

← Browse all free online tools