Check if an IP address appears on major DNS-based email blacklists (DNSBLs). Essential for email deliverability and spam investigation.
🚫 IP Blacklist Checker
An IP blacklist (also called a DNSBL or RBL — DNS Blackhole List / Realtime Blackhole List) is a database of IP addresses associated with spam, malware, phishing, or other malicious activity. Mail servers query these lists in real-time to decide whether to accept or reject incoming connections.
📧 Email Blacklists
Spamhaus, Barracuda, and Sorbs maintain widely-used email blacklists. Being listed here means your mail server's emails will be rejected or sent to spam by most major providers.
🌐 Web Blacklists
Google Safe Browsing, Surbl, and URIBL flag IPs and domains associated with phishing pages, malware distribution, and drive-by download attacks.
🔓 How to Delist
Most blacklists offer a self-service removal form. Fix the underlying issue first (secure the server, stop spam), then submit a removal request with justification.
⏱️ Check Frequency
Monitor your mail server IP weekly. New listings can appear within hours of a compromised account or misconfigured relay sending spam.
❓ Frequently Asked Questions
Why is my IP blacklisted?
Common reasons include: an email account on the server was compromised and used for spam, the server is an open relay, the IP was previously used by a spammer, or your IP range was listed due to a neighbouring IP on a shared hosting block.
How long does delisting take?
Automated delisting usually takes 24–48 hours after the request is approved. Some manual-review lists like Spamhaus may take longer and require detailed remediation evidence.