What This Checker Looks At
It finds the server's IPv4 address (or uses the one you typed) and asks five blocklists whether they have it listed:
- Spamhaus ZEN. The most widely used blocklist on the internet, combining Spamhaus's spam, exploit and botnet lists.
- SpamCop. Built from spam reports by real recipients. Listings expire on their own once the spam stops.
- Barracuda (BRBL). Used by Barracuda's spam firewalls, which sit in front of a lot of business mail.
- PSBL. Fed by spam traps, with simple self-service removal.
- DroneBL. Tracks botnets, open proxies and compromised machines.
Every list has to correctly flag its own test address before its answer counts. If a list is down or refusing queries, it's skipped and left out of the total, so "clean" really means clean on every list shown.
Website IP or Mail Server IP?
Entering a domain checks the address the website resolves to. That's the right check if the same server also sends your email, which is common with cPanel hosting, WordPress sites sending their own mail, and small VPS setups.
If your mail goes through Microsoft 365, Google Workspace or another provider, those IPs are shared and the provider handles them. Bounces mentioning a blocklist are usually about the IP your mail actually left from, so check that one. You'll find it in the bounce message, or in the Received: headers of a sent message.
Listed? Here's the Order to Fix It
1. Stop the spam. Reset passwords on any mailbox that might be compromised, look for unknown forwarding rules, and check web contact forms and scripts that send mail. On a shared server, look at the mail queue for messages you didn't send.
2. Request removal. Use each list's own removal page, linked in the results. SpamCop and PSBL often clear within a day once the spam stops.
3. Re-check. Run this checker again after removal. If an IP keeps getting listed, something is still sending.
Never pay a third party to delist you. Legitimate lists don't charge for removal.
Blacklist FAQ
What is an email blacklist?
A DNS-based blocklist (DNSBL or RBL) is a list of IP addresses seen sending spam or behaving like compromised machines. Mail servers query these lists for every incoming connection, and many reject or junk mail from listed IPs.
Which blacklists does this check?
Spamhaus ZEN, SpamCop, Barracuda (BRBL), PSBL and DroneBL. Each list must pass a self-test before it counts, so a list that's down or refusing queries is skipped rather than reported as clean.
My IP is on the Spamhaus PBL. Is that a blacklisting?
No. The Policy Block List covers home and dynamic IP ranges that ISPs say shouldn't send mail directly. It isn't a spam listing, so this checker doesn't count it. If your mail server sits on such an IP, send through your provider's relay or use a static business IP.
Should I check my website IP or my mail server IP?
For email delivery problems, the mail server's IP is the one that matters. If you use Microsoft 365, Google Workspace or another hosted provider, their IPs are shared and managed by them. Entering a domain checks the IP the website resolves to, which matters if that same server sends mail.
How do I get removed from a blacklist?
Fix the cause first: a compromised account, an open relay, an infected machine, or a form that sends spam. Then use the list's own removal page. SpamCop and PSBL listings usually expire on their own once spam stops. Barracuda and DroneBL have removal request forms. Never pay a third party for delisting.
Why is my brand new server already listed?
Cloud and VPS IPs get recycled. The address you were given may have belonged to a spammer last month. Request removal, and ask your provider for a different IP if a listing won't clear.