DKIM Checker

Look up your DKIM record, detect published selectors, validate the public key and flag weak keys - so you know your mail is properly signed. Free, no signup.

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No credit card required • Instant results

Selector detection

Probes common selectors (Google, Microsoft, Mailchimp…) to find your published DKIM keys.

Public key

Retrieves and parses the p= public key from your DKIM TXT record.

Key strength

Warns on weak keys below 1024-bit, which modern providers may reject.

Missing records

Tells you if no DKIM is published so unsigned mail can be fixed before it bounces.

DKIM FAQ

What is a DKIM selector?

A selector is a label (e.g. google._domainkey) that points to a specific DKIM public key in DNS, letting you rotate keys and run several senders. This tool probes the selectors common providers use.

Why can't DKIM be found?

DKIM is only discoverable if you know the selector. If yours uses a custom selector we don't probe, the record may still exist - check your email provider's DKIM setup for the exact selector name.

Does DKIM replace SPF and DMARC?

No - they work together. DKIM signs the message, SPF authorises the server, and DMARC ties them together with a policy.

Related email tools

SPF CheckerDMARC CheckerMX LookupFull Email Security Check

This is one check. A full scan runs them all.

Free

The DKIM Checker covers one area. A full scan runs every check on the same site in one go, so nothing it does not reach goes unnoticed.

Covered by this check

  • DKIM selector detection
  • Public-key retrieval
  • Key-strength check
  • Missing-record detection

Added by a full scan

  • SPF & DMARC analysis
  • MTA-STS, TLS-RPT & BIMI checks
  • DNS security (DNSSEC, CAA)
  • SSL/TLS certificate validation
  • Security headers analysis
  • Domain reputation analysis
  • Misconfiguration detection
  • Continuous monitoring & alerts
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More email and DNS security tools

SPF Checker

Check an existing SPF record for errors and lookup limits.

DMARC Checker

Validate an existing DMARC record and see how it is configured.

Email Security Checker

Run SPF, DKIM and DMARC checks together in one report.

MX Lookup

Look up the mail servers for any domain.

DNS Lookup

Look up A, AAAA, MX, TXT, NS and other DNS records for any domain.