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Email Deliverability Checker
Enter a sending domain and get an instant, honest read on its SPF, DMARC, and MX records — the authentication that decides whether your cold email lands in the inbox or the spam folder. Read-only DNS lookups. Nothing gets sent.
We strip any https://, paths, or @ — just give us the domain. We never send mail; this is read-only DNS.
Beacon checks deliverability before every send.
Authentication is just the start. Beacon researches every prospect, drafts with evidence, lints each message for deliverability, and lets a human approve — no sequences, no blasting a domain into the spam folder.
More free tools: Cold Email Grader·ICP Builder·ROI Calculator