A blocklist, also called a blacklist or DNSBL, is a public list of IP addresses and domains linked to spam or abuse. Mail servers and security tools use these lists to decide whether to block messages or connections.
This tool checks an IP address or a domain against several lists at the same time, so you can quickly see if emails from it are at risk of being rejected.
Each list returns one of three outcomes.
| Result | Meaning |
|---|---|
| Listed | The list reports this address or domain. |
| Clean | The list does not report it. |
| Unreliable | The list refused the query or did not answer in time. Do not treat this as clean. |
What to do next.
Quick answers about Blacklist Check.
Not necessarily. Lists differ in how strict they are, and an address shared with other users can be listed because of someone else.
The list did not give a usable answer, for example because it limits queries. Try again later.
The domain itself is checked on domain lists, and the IP addresses it points to are checked on IP lists.
No. A clean result only means these lists do not report it right now.