Email authentication

Free DKIM Checker

Look up and validate the DKIM record for any domain and selector — and stop your emails getting flagged as spam.

What is a DKIM record?

DKIM (DomainKeys Identified Mail) adds a cryptographic signature to every email you send. The matching public key lives in a DNS TXT record under a selector, like google._domainkey.yourcompany.com. Receiving servers use it to confirm the message really came from your domain and wasn’t altered in transit.

How to use this DKIM checker

  1. Enter your domain and the selector your sending platform uses (e.g. google, k1, selector1).
  2. Run the check to fetch and parse the published public key.
  3. If it’s missing, copy the key from your email provider and publish it as a TXT record at selector._domainkey.
  4. Re-run the check after propagation.

Why DKIM matters for deliverability

DKIM is the signature behind your sender reputation. Without it, mailbox providers can’t verify you, and your outreach lands in spam regardless of the message. Pair it with SPF and DMARC for a deliverability setup that holds up at scale.

FAQ

How do I check my DKIM record?

Enter your domain and selector above. The tool queries selector._domainkey.yourdomain.com and validates the published public key.

What is a DKIM selector?

A selector is a label that points to a specific DKIM key, so you can run several keys at once (one per sending tool). Your email provider tells you which selector to use.

Why is my DKIM failing?

Common causes: the selector is wrong, the key wasn’t published in DNS, it was split incorrectly, or it hasn’t propagated yet. Re-check the value against what your provider gives you.

Do I need DKIM for cold email?

Yes. Gmail and Yahoo expect SPF, DKIM and DMARC from senders. Skipping DKIM is one of the fastest ways to land in spam.