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post/email-health/v1/blacklist1 credit

DNSBL reputation: reverse the domain's A + MX-host IPs against live-proven public DNSBLs (SpamCop, Barracuda, UCEPROTECT, PSBL, Mailspike, GBUdb, DroneBL, s5h). Spamhaus/CBL are flagged as paid-key-required (public-resolver refused), not queried.

Working example

Parameters

domainrequired

The domain to inspect (a bare host like github.com; a full URL, a leading www., or a full email address are accepted and normalized to the registrable domain).

ipsoptional

Optional explicit IPv4 list (comma-separated or array) to check against the DNSBLs. Omit to auto-resolve the domain's A + MX-host IPs.

request preview

curl -X POST https://api.reefapi.com/email-health/v1/blacklist \
  -H "x-api-key: $REEF_KEY" \
  -H "content-type: application/json" \
  -d '{"domain":"github.com"}'

Hit Send to run this endpoint live.