IP Blocklist Check
Check if an IPv4 address is listed on major DNS-based blocklists (DNSBLs) used by mail servers and firewalls.
About IP Blocklist Checking
DNS-based blocklists (DNSBLs) are used by mail servers, firewalls, and anti-spam systems to identify IP addresses associated with spam, malware, or other abuse. If your IP appears on a blocklist, your emails may be rejected or flagged.
- Spamhaus - The most widely used blocklist, covering spam sources, exploits, and policy violations
- SpamCop - Community-driven list based on user spam reports
- Barracuda - Maintained by Barracuda Networks for spam sources
- SORBS - Identifies open relays, proxies, and spam sources
- UCEPROTECT - Multi-level blocklist with individual IP and range-based listings
This tool checks your IP against 14 major blocklists using DNS queries. A "Listed" result means the blocklist has flagged the IP. Contact the blocklist operator to request removal if your IP is listed incorrectly.
What is an IP Blocklist Check?
IP blocklists (also called blacklists or DNSBLs) are databases of IP addresses known to send spam, host malware, or engage in other malicious activity. Email servers, firewalls, and security services check these lists in real-time to filter out unwanted traffic. If your IP address appears on a blocklist, your emails may be rejected, and your access to certain websites or services may be restricted.
Our tool checks your IP against 14 of the most widely used blocklists, including Spamhaus, SpamCop, and Barracuda. If your IP is listed, it usually means your IP address (or a nearby address in the same range) has been associated with spam or abuse. This can happen even if you haven't sent spam -- shared hosting, compromised devices, or a previously assigned IP can all cause listings.
Major Blocklists We Check
- Spamhaus ZEN - The most widely used blocklist, combining SBL, XBL, and PBL databases
- SpamCop - Community-driven list based on user spam reports
- Barracuda - Maintained by Barracuda Networks based on their email security data
- SORBS - Spam and Open Relay Blocking System, one of the oldest DNSBLs
- UCEPROTECT - Multi-level list that can escalate from individual IPs to entire networks
Frequently Asked Questions
My IP is blocklisted. How do I get removed?
First, identify and fix the issue that caused the listing (compromised account, open relay, malware, etc.). Then visit each blocklist's website and follow their delisting process. Most blocklists like Spamhaus have self-service removal tools. Some lists automatically delist IPs after a period of no further abuse.
Why is my IP on a blocklist if I don't send spam?
Your IP may have been used by a previous owner, your device could be compromised and sending spam without your knowledge, or another user on your shared hosting or network may be the source. Additionally, some blocklists list entire IP ranges, so a neighboring IP's behavior can affect yours.
Does being blocklisted affect my website or just email?
Primarily email delivery. Email servers check blocklists before accepting mail, so a listed IP will have emails rejected or sent to spam folders. Website access is rarely affected, though some security services may show warnings. A VPN can help you access services that block your IP.