100% Free • No Signup • Live DNS

DKIM Checker

Check your DKIM record by domain and selector. Validate the public key, syntax and email authentication configuration.

Find your DKIM selector

Your selector is usually provided by your email service when DKIM is enabled.

Google Workspace

Selector often used:

google

Microsoft 365

Selectors often used:

selector1, selector2

Hosting / cPanel email

Selectors often used:

default, mail, dkim

If these do not work, check your email provider’s DKIM or email authentication settings.

What this checker validates

One check reviews your DKIM selector record, public key and DNS configuration.

DKIM selector record

Check the TXT record at selector._domainkey.yourdomain.com.

Public key presence

Verify that the DKIM record contains a public key value.

DKIM syntax

Validate required tags such as v, k and p.

Key type

Identify RSA or Ed25519 key type where available.

Empty or revoked key

Detect empty public keys, which may indicate a revoked DKIM key.

DNS record format

Check whether the DKIM record is published correctly as a TXT record.

Common DKIM issues this tool can detect

Find DKIM configuration problems that can affect email authentication.

  • MissingDKIM record not found for this selector
  • SelectorWrong selector used
  • Public keyPublic key missing or empty
  • DuplicateMultiple DKIM TXT records found
  • SyntaxInvalid DKIM tag format
  • DNSRecord published at wrong host

How DKIM checking works

DKIM uses a selector to find the correct public key in DNS.

  1. Enter domain and selector

    The selector comes from your email provider. Without a selector, DKIM cannot be checked accurately.

  2. Query the DKIM DNS record

    The tool checks TXT records at selector._domainkey.domain.

  3. Validate the public key

    We check DKIM tags, public key presence, key type and possible configuration issues.

Understanding DKIM selectors

What is a selector?

A label that identifies your DKIM public key in DNS at selector._domainkey.yourdomain.com.

Multiple selectors

Domains can use different selectors for separate mail systems or rotated signing keys.

Preparing DKIM check…

Run focused checks for DNS, email, SSL, domain health and reputation.

Domain Health Checker

Complete domain analysis in one report.

DNS Lookup

Check A, MX, NS, TXT and more.

SPF Checker

Validate SPF records and syntax.

DMARC Checker

Analyze DMARC policy and alignment.

MX Lookup

Find mail exchange records.

Blacklist Checker

Check domain and IP blacklist status.

WHOIS Lookup

Check domain registration details.

SSL Checker

Verify certificate validity and expiry.

Need help fixing DKIM?

Send us your domain report and we’ll review the issue.

Get Help

Frequently asked questions

DKIM is an email authentication method that uses a cryptographic signature to help verify that an email was authorized by the sending domain.
A DKIM selector is a label used to locate the DKIM public key in DNS. The record is usually published at selector._domainkey.domain.com.
No. DKIM records require a selector. If you do not know the selector, check your email provider’s DKIM settings.
It means no DKIM TXT record was found for the selector you entered. The domain may still use DKIM with a different selector.
An empty p= value can mean the DKIM key is revoked or invalid for signing email.
No. The DKIM Checker is free and does not require signup.