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Email Authentication Checker
Check SPF, DKIM, DMARC, and MX DNS records for a domain to find email authentication and deliverability issues.
How to use this email authentication checker
- Enter the domain used in your email From address.
- Add a DKIM selector from your email platform if you want to test a specific DKIM key.
- Review SPF, DMARC, DKIM, and MX results in priority order.
- Update DNS records with your domain registrar, DNS host, or email service provider.
Email Authentication Checker features
- Check SPF records for missing, duplicate, permissive, and high-lookup configurations.
- Check DMARC records for missing policies, duplicate records, monitor-only policies, and enforcement.
- Verify a DKIM selector when your email provider gives you one.
- Show MX records as context for reply, bounce, and report routing.
- Explain what each DNS record does, why it matters, and how to fix common issues.
Why email authentication matters
SPF, DKIM, and DMARC help mailbox providers verify that messages using your domain are legitimate. Good authentication can reduce spoofing risk and helps newsletters, campaigns, and transactional email meet modern sender requirements.
How the checker works
The checker looks up public DNS records for the domain, evaluates SPF and DMARC records on the expected hosts, optionally checks one DKIM selector, and reports the records it found without sending any email.
Email authentication FAQ
What domain should I check?
Check the domain after the @ sign in the From address your subscribers or customers see, such as example.com for hello@example.com.
Where do I find my DKIM selector?
Your email service provider usually shows the selector next to its DKIM setup instructions. Common examples are selector1, google, k1, default, or a provider-specific value.
Does this send a test email?
No. This checker inspects DNS records only. A real inbox placement test can still be useful after your DNS records are correct.
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