IP Blacklist Check

Query major DNS-based block lists (DNSBLs) for an IPv4 address. Leave blank to check your current public IP.

IPv4 only for DNSBL lookups. Results depend on the C# backend API.

About DNSBL checks

A DNS-based Blackhole List (DNSBL) publishes IP addresses associated with spam, malware, open proxies, or other abuse. Mail servers and security tools query these lists by reversing the IP octets and looking up a DNS name under the list’s zone (for example 4.3.2.1.zen.spamhaus.org).

This widget queries a set of widely used public lists. A listing does not always mean the IP is malicious — shared hosting, dynamic ranges, and false positives occur. Always review the list operator’s documentation before taking action.

Lists included

  • Spamhaus ZEN — Combined SBL / XBL / PBL
  • SpamCop — bl.spamcop.net
  • Barracuda — b.barracudacentral.org
  • SORBS — dnsbl.sorbs.net and related zones
  • PSBL — psbl.surriel.com
  • UCEPROTECT — Level 1
  • Mailspike — bl.mailspike.net
  • SpamRats — dyna / noptr / spam zones
  • DroneBL — dnsbl.dronebl.org
  • blocklist.de — bl.blocklist.de
  • s5h.net — all.s5h.net
  • JustSpam — dnsbl.justspam.org
  • InterServer RBL — rbl.interserver.net