RBL

DNSBL / Blacklist Check

Check whether an IPv4 address is on public spam/abuse blocklists.

● runs on our server

IPv4 address

Checks an IPv4 address against public DNS blocklists (DNSBLs/RBLs) in parallel, on utly's server. No third-party reputation API. Mail-server operators use these lists to decide whether to accept your mail.