This DKIM checker page helps you verify domain selectors, TXT records, and signing readiness before deliverability drops.

What to validate with a DKIM checker

  • Selector DNS TXT record exists
  • Public key syntax is valid
  • Selector name matches your sending platform
  • DKIM alignment supports your DMARC policy

DKIM troubleshooting flow

  1. Identify the selector from your ESP or SMTP provider
  2. Query
  3. Verify a valid and key value
  4. Send a test email and inspect headers for

Common DKIM problems

Wrong selector

Teams often publish one selector and send with another. Confirm the selector in message headers matches DNS.

Truncated key value

Long TXT records can be wrapped incorrectly when copied between providers. Re-check quoting and formatting.

Missing rotation process

Without key rotation, compromised keys remain valid longer than needed. Define a regular selector rotation cadence.

Next step for production teams

Combine DKIM validation with SPF and DMARC checks in one workflow using MailSlurp authentication monitoring.