How do I check if my DKIM record is set up correctly?

Enter your domain and DKIM selector in the DKIM Checker to validate the published public key record.

Where do I find my DKIM selector?

Your email provider's setup docs or admin console list the selector — for example, Google Workspace typically uses 'google'. You can also inspect the DKIM-Signature header of a sent email.

Do I need DKIM if I have SPF?

Yes — SPF and DKIM authenticate mail differently, and DMARC requires at least one of them to align with your domain. DKIM survives forwarding better than SPF, so both are recommended.

DNS & NETWORK TOOLS · FREE ONLINE TOOL

DKIM Checker

Verify DKIM records and inspect the public key for any domainEvery legitimate email should be cryptographically signed by its sender. DKIM attaches a signature to each outgoing message, verified against a public key in your DNS. This tool looks up selector records and validates what it finds.

✓ Free to use✓ No sign-up✓ Ready in your browser

// DKIM CHECKER · GET STARTED

Use DKIM Checker

Verify DKIM records and inspect the public key for any domain

// DKIM CHECKER · AT A GLANCE

DKIM Checker: what to know first.

Verify DKIM records and inspect the public key for any domain

01
DKIM is the cryptographic half of email authentication: it proves a message really came from your domain and was not altered in transit. The public key lives in DNS, so a missing or malformed record silently breaks authentication and pushes your mail toward the spam folder. The DKIM Checker queries the exact selector hostname your provider uses and validates the record the way receivers do.
02
Beyond a simple valid-or-missing answer, the tool parses every tag in the record, reports the public key length and approximate RSA key size, and flags testing flags or non-standard key types. That makes it useful both for initial setup, when you are confirming a provider record went live, and for audits, when you are checking that old selectors were cleaned up properly.

// DKIM CHECKER · HOW IT WORKS

How to use the DKIM Checker

Enter domain and selector

Enter the domain and the DKIM selector from your email provider (default is "default").

Run the check

Click "Check DKIM" to query the live TXT record at selector._domainkey.yourdomain.

Review key details

Read the verdict, the public key size, and the parsed tag details.

// DKIM CHECKER · ABOUT THIS TOOL

About the DKIM Checker

DKIM is the cryptographic half of email authentication: it proves a message really came from your domain. A missing or malformed record silently pushes your mail toward the spam folder.

The DKIM Checker queries your provider's selector hostname and validates the record the way receivers do, parsing every tag and reporting the key size.

Where it helps most

Catching the silent failures that sink deliverability.

Provider migrations

When you switch email providers, the old selector keeps working while the new one must be published first; confirm it is visible before sending.

Deliverability drops

When deliverability drops, a broken or missing DKIM record is one of the first things to verify, right alongside SPF and DMARC.

Agency audits

Agencies managing dozens of client domains use it as a quick pre-send audit before any campaign ever goes out to clients.

Post-DNS-change checks

Sysadmins use it after DNS changes to make sure selectors were published correctly and mail keeps flowing without any interruption.

Reading the report

What gets flagged.

Key format

The checker retrieves the live TXT record, parses the public key, and checks that it is properly formatted for sending.

Weak keys

It flags records that are too short for modern security standards, selectors that return nothing, and syntactically broken keys too.

Missing selectors

Selectors that return nothing at all are reported plainly, so you know the record is missing rather than broken entirely.

DKIM Checker: built for trust

Enter your domain and selector for a live lookup of the TXT record, parsed and validated in seconds.

// DKIM CHECKER · COMMON QUESTIONS

DKIM Checker FAQs

What is a DKIM selector?

A selector is the label in the DKIM DNS record, such as selector._domainkey.yourdomain.com, that tells receivers which public key to use for verification. Providers assign selectors when you set up signing, for example google for Google Workspace or selector1/selector2 for Microsoft 365.

How do I find my DKIM selector?

What DKIM key length is considered secure?

Why is DKIM failing even though my record exists?

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