Blacklist Check
This free blacklist check looks up an IP address, or a domain's web and mail server addresses, on nine public DNS blocklists and shows where it's listed and how to get removed.
What is an email blacklist?
An email blacklist (also called a blocklist or DNSBL) is a public list of IP addresses and domains that have sent spam or been compromised. Mail servers check these lists for every incoming connection.
If your mail server's IP is listed, your messages may be refused or sent to spam until it's removed. A new server can inherit a listing from the address's previous user, so it's worth checking before you start sending.
Which blocklists we check, and which we don't
We check SpamCop, Barracuda, PSBL, UCEPROTECT Level 1, Mailspike, DroneBL and s5h.net for IP addresses, and SURBL and NordSpam for domain names. For a domain, we check up to four of its website and mail server addresses.
We don't check Spamhaus. It refuses lookups that arrive through public DNS resolvers, so any answer we got would be meaningless; check it directly on spamhaus.org. When a list doesn't answer, we say we couldn't check it, rather than guessing.
What to do if you're listed
Find and fix the cause first: an infected computer, a hacked website or contact form, a mailbox with a stolen password, or a mailing list people didn't sign up for. If you ask to be delisted before that, you'll just be listed again.
Then use the delisting link next to each listing. Some lists, like SpamCop, remove entries on their own once the spam stops; others have a request form. On shared hosting, contact your host, because the server's address is shared and they handle it.
Frequently asked questions
Why does one list show me as listed when the others don't?
Each list has its own sources and rules. Some list single addresses after a few spam reports, others list whole networks. One listing on a smaller list rarely blocks much mail, but check what caused it.
What does "couldn't check" mean?
The list didn't answer in time, or refused the lookup. It isn't a listing. Try again a little later.
Can I check an IPv6 address?
Not here yet. The lists we check are IPv4 lists. Enter your domain instead, and we'll check the IPv4 addresses of its website and mail servers.
How do I find my mail server's IP address?
Enter your domain and we look up its mail servers for you. To find the address that actually sent a message, paste the message's headers into the email header analyzer and look at the first hop.
Can I see what a listing looks like?
Yes: enter 127.0.0.2. Every blocklist lists that test address on purpose, so you'll see listed results and delisting links.