Blacklist checker: is your domain or mail server on a blocklist?
Enter a domain or IP address and you immediately see whether it is on a well-known email blocklist, such as Spamhaus, Barracuda, SpamCop or URIBL. For a domain, we also check the IP addresses of its mail servers. No sign-up needed.
For a domain, we check the domain against the domain lists, and the IPv4 addresses of its mail servers (MX) and of the domain itself against the IP lists, up to four addresses.
A listing hurts your delivery, but the cause usually runs deeper: missing authentication, a compromised account or an outdated mailing list. So check your SPF, DKIM and DMARC as well.
Check SPF/DKIM/DMARC About deliverabilityIf an address is on such a list, many recipients reject or filter your mail. Below the result you read what a listing means and how to get off it again.
What if you are listed?
Requesting delisting without removing the cause rarely helps: the list puts you back on at the next spam, often for longer. So work in this order.
1. Find the cause
See which list mentions you and why: the list page usually shows the reason. Typical causes are a compromised mail account, an infected computer or website, an open relay or sending to purchased or outdated addresses.
2. Fix the problem
Change leaked passwords, clean infected devices, close open relays and clean up your mailing list. Set up SPF, DKIM and DMARC, so others cannot abuse your domain unchecked.
3. Request delisting
Use the form on the list page. Some lists remove you automatically once no new reports come in, others ask for a short explanation of what you have changed.
4. Check again
After delisting, it can take a few hours for DNS caches to update. Then check again and keep an eye on your bounces: a new rejection that names a list points to a new listing.
IP lists and domain lists
Receiving mail servers consult both types of list. Each checks something different, and a listing on just one of them can be enough to have your mail rejected.
DNSBL
IP lists (DNSBL) list the server that sends. A recipient queries them on every connection. A listing affects all mail from that IP address, including mail from other domains on the same server.
URIBL / DBL
Domain lists (URIBL, SURBL, Spamhaus DBL) list domains that appear in spam, as the sender or as a link. They follow your domain, even if you switch sending servers.
?
Unknown means the list returned no usable answer, for example because it was temporarily unreachable. Not checked means that list was not queried this time. Neither says anything about a listing.
How this checker works
The tool performs the same DNS lookup a receiving mail server performs, directly at the blocklists. We do not use your input for marketing. To prevent abuse, we keep each check with the visitor's IP address in a log for 90 days. The result is cached for 15 minutes and the number of checks per visitor is limited.
The checker queries a selection of widely used lists, not a complete list of all blocklists. It checks IPv4 addresses; IPv6 and the reputation scores of the large mailbox providers are out of scope.