Can someone send email as your company?
SPF, DKIM, DMARC and more. Free, no sign-up.
Questions
What do SPF, DKIM and DMARC do?
SPF lists the servers that can send for your domain. DKIM signs each message. DMARC tells the receiver what to do with email that fails: deliver it, send it to spam or reject it.
Why does DMARC reject matter?
Only p=reject makes the receiver refuse fake email. With p=none, a fake invoice or payment request that uses your domain still reaches the inbox.
Do you keep the domain I check?
No. We read public DNS records and keep only anonymous totals, such as how many checks found DMARC on reject. We do not save the domain or who checked it.
Why was no DKIM key found?
Each provider chooses the name (selector) of its DKIM key. We test the common names, such as google, selector1, selector2, default, k1 and mail. If your provider uses another name, look for it in your provider's settings.
Can an agent run this check?
Yes, free: GET /api/email-check?domain=yourcompany.com, or the commsharbor_email_security_check tool on our MCP server.
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