Is DKIM configured for your selector - verify the public key before signed mail fails.
Find it in your email provider's DKIM settings (e.g. 'google', 'mail')
Whether the selector resolves in DNS
Valid signing key published for your domain
Syntax issues that break verification
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Email signing records explained
When DKIM signing breaks, receivers cannot verify message integrity - authenticated mail fails and inbox placement drops, often after a provider migration or key rotation.
A DKIM checker looks up the public key at selector._domainkey.yourdomain.com and validates the record your email provider published. Enter the selector your ESP documents for accurate results.
Run a free DKIM check after configuring outbound mail or rotating keys. Add domains to TotalSiteControl monitoring for alerts when signing records change or disappear.
Free TotalSiteControl monitoring - email alerts, no credit card required.
Get notified when signing records or selectors change.
Scheduled validation catches key rotation issues early.
See past DKIM results for email deliverability audits.
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It looks up the DKIM DNS record for a domain and selector, validating the public key used to verify cryptographically signed email.
Yes. Enter a domain and selector for instant results - no signup, no credit card, and no limit on one-off checks.
A label that identifies which DKIM public key to use. It's part of the DNS lookup name, e.g. google._domainkey.yourdomain.com.
Check your email provider documentation - Google uses google, Microsoft often uses selector1, and many ESPs use default.
Wrong selector, a missing DNS record, or a key that has not propagated yet after setup. Confirm the exact record your provider published.
Yes - SPF and DKIM solve different problems. Use both plus DMARC for full email authentication.
Your email provider generates a public key. Add the TXT record they supply at selector._domainkey.yourdomain.com, then verify here.
After email provider changes or key rotation. Monitoring alerts when DKIM records change or disappear.