Spam list query
Spam blacklist servers maintain lists of addresses from which large quantities of spam are sent. Spam blockers such as SpamAssassin query these lists in order to be able to reject emails sent from such addresses. This tool enables you to check whether an address is on one of the lists used by default by SpamAssassin or on one of the lists for iX's NiX Spam project.
The DNS protocol is used to make this query, for which reason these lists are known as DNS blacklists (DNSBL).
The response to the DNS query is an IP address from the 127.0.0.0/8 loopback address subnet. The last byte indicates whether the server is on the list and why.
If you enter an IP address, the following lists are queried: