Check if an IP address is listed on email and spam blacklists
An IP blacklist (also called DNSBL or RBL - DNS-based Blackhole List) is a database of IP addresses known to send spam or malicious content. Email servers and spam filters check these lists to block unwanted mail.
If your IP is blacklisted, your emails may be rejected or sent to spam folders. This tool checks your IP against 15+ major blacklists to help you identify and resolve deliverability issues.
An IP blacklist (also called a DNSBL or blocklist) is a database of IP addresses known to send spam or malicious content. Email servers check these lists to decide whether to accept or reject incoming mail from a given IP.
Common reasons include sending spam (even unknowingly from a compromised device), being on a shared IP with a spammer, running an open mail relay, malware infection, or your IP's previous owner having a bad reputation.
First, fix the underlying issue (malware, open relay, etc.). Then visit each blacklist's website and follow their delisting process. Most blacklists like Spamhaus and Barracuda have self-service removal forms. Some lists automatically delist after a waiting period.
Check weekly if you run a mail server, monthly for general business use. Set up automated monitoring if email deliverability is critical to your business. Our tool scans 15+ major blacklists simultaneously for comprehensive coverage.
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