Last updated October 12, 2026 · Report an error
DKIM (DomainKeys Identified Mail) lets a domain cryptographically sign outgoing email, proving it wasn't altered in transit and really came from an authorized sender. This tool checks whether a domain has published a DKIM record for a specific selector.
How it works
Unlike SPF or DMARC, a DKIM record's location depends on a "selector" — a short name chosen by whoever configured DKIM for that domain — published at "{selector}._domainkey.{domain}" as a TXT record starting with "v=DKIM1". Enter the domain and the selector you want to check (your email provider's DKIM setup guide will tell you which selector it uses), and the tool looks up that exact location.
- Enter domain.
- Enter dKIM selector.
- Click Calculate to see your results.
Examples
Why the selector matters
The same domain can have multiple DKIM selectors active at once (e.g. one per email-sending service) — checking the wrong selector name will correctly report "not found" even if DKIM is properly configured under a different selector.
Who should use it
- Verifying DKIM is correctly published after setting it up with an email provider.
- Diagnosing email deliverability or authentication issues.
Industry applications
- Email deliverability and security
- IT support and DNS administration
Advantages
- Instant check with no software installation.
- Extracts the key type for a quick sanity check of the record's content.
Limitations
- Requires knowing the exact selector in advance — there's no way to discover an unknown selector through DNS alone.
Common mistakes to avoid
- Guessing a selector rather than checking your email provider's actual DKIM setup instructions for the correct one.
- Checking only one selector and concluding DKIM isn't configured at all, when a domain may have several selectors for different sending services.
Best practices
- Get the exact selector from your email provider's DKIM setup documentation rather than guessing.
- Check DKIM alongside SPF and DMARC for a complete picture of a domain's email authentication.
Tips
- Use alongside the SPF Record Checker and DMARC Record Checker tools for a complete email-authentication audit of a domain.