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Enter any domain and get an instant DNS health report. We check the records that decide whether your emails land in the inbox or spam — and tell you exactly what each result means.
Enter a domain to check all DNS records relevant to email deliverability. Uses Google DNS and Cloudflare DNS-over-HTTPS for accurate, real-time results.
What we check
SPF
Tells receivers which IPs are authorised to send for your domain. A missing or broken SPF is a top cause of spam-folder placement.
DKIM
A cryptographic signature proving your emails weren't tampered with in transit. Required for DMARC. Without it, your authentication chain breaks.
DMARC
The policy layer telling receivers what to do with emails that fail SPF/DKIM — reject, quarantine, or pass. A missing DMARC leaves your domain unprotected.
MX + Routing
MX records direct inbound mail to the right server. Misconfigured MX records cause bounced replies, broken contact forms, and missed emails.
Understanding your results
The result column above tells you which records exist. This section tells you what each one does for your deliverability.
SPF tells receiving servers which IP addresses are allowed to send email for your domain — a whitelist in DNS. When SPF fails, many servers route your email to spam or reject it outright.
DKIM adds a cryptographic signature to outgoing emails. Receivers verify it against your public key in DNS. Mismatch flags the message as tampered or forged.
DMARC tells receivers what to do with emails that fail SPF or DKIM — reject, quarantine, or let through. It also pipes you reports on who is sending from your domain.
MX records define which mail servers receive email for your domain. Without valid MX records, no one can reply to your emails. Multiple records with priority values give redundancy.
DNS is step one
Your DNS records are the foundation. Brain monitors the full deliverability stack — ESP signals, blacklists, DMARC reports, Postmaster, SNDS — and tells you exactly what to fix when inbox rates drop.
