Remote

Email Authentication Checker

Enter your domain to check SPF, DMARC, DKIM and MX records. You can optionally add a DKIM selector for a custom check. The tool will also try common DKIM selectors for popular email providers and relay services.

Just the domain, no http/https.
If provided, we’ll look for a DKIM record at selector._domainkey.domain.

This tool will also try common DKIM selectors for popular providers: Microsoft 365 (selector1, selector2), Google Workspace (google, default), Brevo / Sendinblue (mail), SendGrid (s1, s2), Mailchimp / Mandrill (k1, k2), Mailgun (mg), Postmark (pm), Constant Contact (ctct1, ctct2), iCloud custom domains (sig1). Results are best-effort guesses – some providers use custom or random selectors per domain.