dnsbl
guide

The following are DNSBLs (and other anti-spam tools) that we recommend. Being listed on this page does not necessarily mean that we use the particular DNSBL (or tool) in our own filtering. Also, some of these are better for scoring while others are appropriate for blocking. At this time, minimal commentary will be presented, but that may change in the near future. Also, please visit each web site to gain a full understanding of the licensing requirements for each of these. At various usage levels, some of these are not free or have particular requirements.

Sender’s IP DNSBLs:

• ivmSIP - the invaluement Sender’s IP list (our own!)
• Zen (SpamHaus)
  • CBL - The most effective and prolific data feed into Spamhaus’ Zen list. If you already use Zen, then it is best to not query CBL since Zen already includes CBL. But CBL is available as a stand-alone DNSBL.
• SpamCop
• PSBL
• SORBS
• NJABL
• UCEPROTECT
• HostKarma
• dnsbl.net.au
• WPBL

URI DNSBLs:

• ivmURI - the invaluement URI list (our own!)
• SURBL
• URIBL

Specialty DNSBLs:

• backscatterer.org - NOT to be used for either blocking or scoring... unless other attributes of the message indicate that the message might be backscatter.

dnsbl
guide