IP Blacklist Checker
Check if an IP address is listed on major email blacklists (RBLs/DNSBLs). IP blacklisting can severely impact email deliverability from that server.
Understanding IP Blacklists
IP blacklists (also called RBLs or DNSBLs) are databases of IP addresses known to send spam or malicious content. Email servers check these lists in real-time to decide whether to accept, filter, or reject incoming connections.
Why IPs Get Blacklisted
- Sending spam or bulk unsolicited email
- Compromised servers being used by spammers
- Open relays or misconfigured mail servers
- IP ranges with historically bad reputation
- Shared hosting with other bad actors
Blacklists We Check
We check against Spamhaus ZEN, Spamcop, Barracuda, SORBS, SpamEatingMonkey, UCEPROTECT, Mailspike, and JustSpam.