List of All Known DNS-based Spam Databases. The most common way of detecting spam is by using spam databases (blacklists, sometimes incorrectly referred to as RBLs, since RBL is trademarked by MAPS) that list the addresses of mail servers known (or believed) to send spam. This is done by taking the IP address of the remote mail server, converting it to a domain name using the ip4r format (1.2.3.4 becomes 4.3.2.1.bl.example.com), and seeing if that name exists. Full details on this format are available here.

The following are the ip4r DNS lookup services that we know about. This is one of the two comprehensive lists of DNS-based spam databases (the other being http://moensted.dk/spam). Know of a spam database not listed here? Please E-mail us. You can go to www.DNSstuff.com to quickly look up an IP in all of the databases, using the Spam Database Lookup. Or, find out more about Declude JunkMail one of the most advanced anti-spam programs available.

Name/link	A	TXT	Free	OK	Lookup Domain	Returns	Description
0SPAM					0spam.fusionzero.com	[various]	Hand picked mass E-mail IP's and some networks that do not enforce spam rules on clients. Returns 127.0.0.1 for a single IP, 127.0.1.0 for a Class C range, or 127.1.0.0 for a Class B range. Verified 24 Feb 2004.
AHBL					dnsbl.ahbl.org	[various]	Abusive Hosts Blocking List. Lists abusive Internet hosts. Updated by hand. Includes many response codes indicating why the IP was listed. Confirmed 127.0.0.2 test entry on 03 Nov 2003. Was originally SUMMIT. Note: If you are concerned about large blocks, please use the ircbl.ahbl.org which is just the bare minimum dnsbl list with nothing but open proxies, open relays, comprimised machines, ddos drones, trojans.
ASPEWS					aspews.ext.sorbs.net	[127.0.0.2]	This list has been provided to replace the seemingly defunct Spam Prevention Early Warning System (SPEWS) list. This list is not connected or related to the Anonymous Postmasters Early Warning System (APEWS) list.
BGISOCBL					dnsbl.isoc.bg	[unlisted]	Bulgarian Spam Prevention System. Designed primarily to protect isoc.bg's members from receiving Bulgarian spam. Warning: Is not testable.
CBL					cbl.abuseat.org	[127.0.0.2]	Lists IPs that send to large spamtraps, and are running open proxies, worms/viruses, trojan horses, etc. Confirmed 01 Aug 2003.
CLUECENTRAL					*.rbl.cluecentral.net	Unknown	Lists IPs in certain countries. Missing test entry 127.0.0.2. Confirmed 18 Jun 2002 Warning: Is not testable.
CSMA					bl.csma.biz	127.0.0.2	Lists IPs of mailservers that send spam twice in a short timeframe to the McFadden Associates mailservers. Confirmed 29 Sep 2003.
CSMA-SBL					sbl.csma.biz	127.0.0.2	Lists IPs of mailservers that send spam to the McFadden Associates mailservers, even once. More aggressive than the CSMA test, and best used with score-based anti-spam programs. Confirmed 20 Oct 2003.
CYBERLOGIC					dnsbl.cyberlogic.net	127.0.0.2	Blocking list used to prevent reoccuring spam sent to Cyberlogic. Nominations come from their clients by submitting a spam. Confirmed 28 Nov 2003.
DEADBEEF					bl.deadbeef.com	127.0.0.2	Lists ISPs that have no way to report abuse. Confirmed 11 Mar 2003.
DNSBLINFO					spamsources.dnsbl.info	[unlisted]	An experimental private list. Lists entire netblocks. Confirmed 06 Feb 2004.
DNSBLNETAUOHPS					ohps.dnsbl.net.au	[Unknown]	Reynolds Open HTTP Proxy Server Block List. Lists servers that have open web proxies that are being abused. Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAUOMRS					omrs.dnsbl.net.au	[Unknown]	Reynolds Open Multi-Level Relay Server Block List. [*Both ip4r and rhsbl*] Lists servers that are open multi-level relays and being abused. Unclear where the domains come from (RHSBL, reverse DNS, HELO, etc.). Also appears to list open proxies.. Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAUOSPS					osps.dnsbl.net.au	[Unknown]	Reynolds Open Socks Proxy Server Block List. [*Both ip4r and rhsbl*] Lists servers that have open socks proxies that are being abused. Unclear where the domains come from (RHSBL, reverse DNS, HELO, etc.). Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAUOSRS					osrs.dnsbl.net.au	[Unknown]	Reynolds Open Single-level Relay Server Block List. [*Both ip4r and rhsbl*] Lists servers that are open relays and being abused. Unclear where the domains come from (RHSBL, reverse DNS, HELO, etc.). Also appears to list open proxies. Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAUOWFS					owfs.dnsbl.net.au	[Unknown]	Reynolds Open Web Form Server Block List. [*Both ip4r and rhsbl*] Lists servers with web form scripts that have been abused. Unclear where the domains come from (RHSBL, reverse DNS, HELO, etc.). Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAUOWPS					owps.dnsbl.net.au	[Unknown]	Reynolds Open Wingate Proxy Server Block List. Lists servers that have open wingates that are being abused. Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAURDTS					rdts.dnsbl.net.au	[Unknown]	Reynolds Dialup/DSL Type Services Block List. Lists dialup, DSL, and other dynamic IP ranges. Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAURICN					ricn.dnsbl.net.au	[Unknown]	Reynolds Incorrectly Configured Networks. Lists networks which appear to be incorrect configured. Includes networks with no/few reverse DNS entries, or lots of spam. Appears to list Class C ranges (dangerous!) rather than assigned network ranges. Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAURMST					rmst.dnsbl.net.au	[Unknown]	Reynolds Multiple Spam Traps Block List. [*Both ip4r and rhsbl*] Lists IPs/domains that send to spamtraps. Unclear where the domains come from (RHSBL, reverse DNS, HELO, etc.). Free for first 1,000 lookups per day. Confirmed on 24 Jan 2003.
DNSBLNETAUT1					t1.dnsbl.net.au	[Unknown]	Reynolds 'Type 1' Block List. Lists servers that are listed in any of the other Reynolds lists. Free for first 1,000 lookups per day. Confirmed on 23 Jan 2003.
DNSRBL-DUN					dun.dnsrbl.net	[various]	Lists dialup lines (modems, DSL, cable). Warning: uses 127.0.0.1 as its test entry. Verified 19 Jun 2002.
DNSRBL-SPAM					spam.dnsrbl.net	[various]	Lists known spammers, based on E-mail sent to 'honey pot' addresses. Warning: uses 127.0.0.1 as its test entry. Verified 19 Jun 2002.
DUINV					duinv.aupads.org	[unlisted]	Lists IPs that belong to dialup connections. No TXT records, missing test entry 127.0.0.2. Warning: Is not testable.
DULRU					dul.ru	[unlisted]	Apparently lists dialup lines in Russia (site is in Russian). No TXT records, missing test entry 127.0.0.2. Warning: Is not testable.
FABELSOURCES					spamsources.fabel.dk	127.0.0.2	Lists networks (mostly in Asia and South America) that keep sending spam. Confirmed on 23 Jan 2002.
FIVETENFREE					blackholes.five-ten-sg.com	127.0.0.12	Lists mailservers used by free mail services that either have no abuse address address listed at abuse.net, or that ignore abuse complaints.
FIVETENIGNORE					blackholes.five-ten-sg.com	127.0.0.7	Lists IP ranges of companies that ignore spam complaints. Warning: May block large ISPs.
FIVETENKLEZ					blackholes.five-ten-sg.com	127.0.0.10	Lists mailservers that send AV notification responses to Klez and similar viruses that forge the return address.
FIVETENMULTI					blackholes.five-ten-sg.com	127.0.0.5	Lists multi-stage open relays.
FIVETENOPTIN					blackholes.five-ten-sg.com	127.0.0.4	Lists bulk mailers that don't use confirmed opt-in.
FIVETENOTHER					blackholes.five-ten-sg.com	127.0.0.9	Lists servers with 'other issues.'
FIVETENSINGLE					blackholes.five-ten-sg.com	127.0.0.6	Lists single-stage open relays.
FIVETENSRC					blackholes.five-ten-sg.com	127.0.0.2	Lists direct spam sources. WARNING: Lists entire Class B ranges if 1 IP sends them spam!
FIVETENTCPA					blackholes.five-ten-sg.com	127.0.0.11	Lists companies that violate the TCPA act, by leaving pre-recorded telephone sales calls or not maintaining a do-not-call list.
FIVETENWEBFORM					blackholes.five-ten-sg.com	127.0.0.8	Lists servers running vulnerable web scripts that can send spam.
GIRL					relays.bl.gweep.ca	[unlisted]	Gweep.ca Insecure Relay List. Lists open relays. No TXT records, no 127.0.0.2 test entry. Warning: Is not testable.
GRIP					random.bl.gweep.ca	[unlisted]	Randomly lists random IPs. Obviously, this should not be used as a spam test. No TXT records, no 127.0.0.2 test entry. Warning: Is not testable.
HIL					hil.habeas.com	127.0.0.2	Lists IPs of mailservers that infringe on Habeas' intellectual property, and are unwilling or unable to rectify the situation in a timely matter. Confirmed 30 Oct 2002.
HILLI					blocked.hilli.dk	[unlisted]	Undocumented.
HOSTKARMA					hostkarma.junkemailfilter.com	127.0.0.2	Free DNS host karma listing servers to provide information to the world about what servers are sending spam, nonspam, or a mix of spam and nonspam. This is a service of http://www.junkemailfilter.com one of many technologies used in advanced email filtering.
ICMFORBIDDEN					forbidden.icm.edu.pl	[unlisted]	Lists IPs of companies that took ORBS to court. No TXT records, no 127.0.0.2 test entry. Warning: Is not testable.
INFORMATIONWAVE					blacklist.informationwave.net	[unlisted]	Lists spammers. No TXT records, no 127.0.0.2 test entry. Warning: Is not testable.
INTERSIL					blackholes.intersil.net	127.0.0.2	Undocumented (but confirmed).
INVALUEMENT-IVMSIP					RSYNC Access Only	[unlisted]	Commercial list which requires a subscription. Free test available. Extremely good at catching snowshoe and other fly-under-the-radar spams missed by all other low-FP DNSBLs. FP rate is extremely low, comparable with Zen.
INVALUEMENT-IVMSIP24					RSYNC Access Only	[unlisted]	Commercial list which requires a subscription. Free test available. Similar to ivmSIP, but more aggressive because this list attempts to catch snowshoe spam *preemptively*. The FP is almost as low as the ivmSIP FP-rate, but it might be better used for scoring instead of blocking.
IPWHOIS					ipwhois.rfc-ignorant.org	127.0.0.6	Lists domains that have incorrect or otherwise bad information in their IP whois data. Note that this MAY have the same flaw as the BADWHOIS test and could list major portions of the Internet.
JAMMDNSBL					dnsbl.jammconsulting.com	[various]	Currently undocumented. Returns 127.0.0.2 for spammers, .3 for open relays, .4 for insecure E-mail scripts, .5 for open proxies, and .6 for dynamic IP ranges. WARNING: Lists IP ranges for some entire countries.
KEMPTBL					dnsbl.kempt.net	127.0.0.2	Lists any mailserver that sends spam or E-mail with forged headers. They recommend contacting them before using it, so you can be notified of changes. Warning: Is not testable.
KITHRUP					3y.spam.mrs.kithrup.com	0.0.0.0	Unknown. Note the possibly odd '0.0.0.0' response that could break existing anti-spam programs.
KUNDENSERVER					relays.bl.kundenserver.de	127.0.0.2	Run by a large web hosting company that tests mailservers that connect to it, to see if they are open relays. Lists the open relays for several weeks/months.
LNSGBLOCK					spamguard.leadmon.net	127.0.0.7	Lists blocks of addresses that may contain spammers, but only if there are no reverse DNS entries. Confirmed test entry on 08 Jan 2002.
LNSGBULK					spamguard.leadmon.net	127.0.0.4	Lists bulk mailers that don't have confirmed opt-in, or that allow spam to be sent. Confirmed test entry on 08 Jan 2002.
LNSGDUL					spamguard.leadmon.net	127.0.0.2	Lists dialup lines (remember, DUL-type tests should NOT be run against local users). Confirmed that the zone exists on 30 Oct 2001, confirmed test entry on 08 Jan 2002.
LNSGMULTI					spamguard.leadmon.net	127.0.0.6	Lists multiple stage open relays that are not on other spam databases. Confirmed test entry on 08 Jan 2002.
LNSGOR					spamguard.leadmon.net	127.0.0.5	Lists single-stage open relays that are not on other spam databases. Confirmed test entry on 08 Jan 2002.
LNSGSRC					spamguard.leadmon.net	127.0.0.3	Lists spam sources (any mail server sending spam). Confirmed test entry on 08 Jan 2002.
MAILDEFLECTOR					[unlisted]	127.0.0.2	A pay service that lists IPs based on spambait addresses and customer submissions. Customers can add/remove IP ranges and/or countries for their own use, using a simple checkbox list. $150/year/server, 60 day free trial (free for non-profits/hobbyists). Warning: Is not testable.
MAPS-DUL					dialups.mail-abuse.org	127.0.0.3	MAPS DUL (Dialup User List) was another very important ip4r DNS lookup, but since it now requires a subscription, other dialup tests may be used instead. It lists the IP addresses of lots of 'dialup lines' -- the connections that individuals get when then dial into the Internet. Although lots of legitimate E-mail originates from dialup lines, legitimate users very rarely if ever send mail directly to the receiving SMTP server; they send mail to their ISP's mail server. Therefore, it is safe to say that if anyone listed in DUL connects to your mail server, they are not sending legitimate E-mail. We recommend using the DUL test. A pay service as of 7/31/2001. Warning: Is not testable.
MAPS-NML					[Unlisted]	[Unlisted]	MAPS NML (Non-confirming Mailing List) lists mail servers that send out mailing list E-mail for lists that do not confirm the subscriptions. Mailing lists that send E-mail without confirming will often end up sending spam, as people think it is a cute practical joke to add their friends to the list.A pay service. Unconfirmed. Warning: Is not testable.
MAPS-OPS					[Unlisted]	[Unlisted]	MAPS OPS (Open Proxy Stopper) lists computers that are running open proxies. A pay service. Unconfirmed. Warning: Is not testable.
MAPS-RBL					blackholes.mail-abuse.org	127.0.0.2	MAPS RBL (Realtime Blackhole List) was once the most important ip4r DNS lookup, but it is less used now that it requires a subscription. It lists networks known to be friendly or neutral to spammers. In most cases, it is very good about only listing mail servers that send out a lot of spam, and not simply open relays that get hijacked once and then are secured. Because of this, we recommend using the RBL test. A pay service as of 7/31/2001. Warning: Is not testable.
MAPS-RBLPLUS					rbl-plus.mail-abuse.org	[unlisted]	MAPS RBL+ is a paid service that apparently combines RBL, RSS, DUL, and OPS into a single lookup. It appears that you can't test it without a subscription. Warning: Is not testable.
MAPS-RSS					relays.mail-abuse.org	127.0.0.2	MAPS RSS (Relay Spam Stopper) lists spam-relaying mail servers. These are open relays that have been known to send spam. They may well be legitimate mail servers that were open relays, and may be closed soon. However, they were open relays and did send spam. This is similar to RBL, except that the mail servers may be anti-spam and quick to fix the problem. In that case, you may be blocking legitimate mail until the problem is fixed. There is no grace period, so if the server is caught sending spam and is still an open relay, it will be listed immediately. In June, 2001 it contained about 100,000 mail servers! A pay service as of 7/31/2001. Warning: Is not testable.
MAPS-QIL					[unlisted]	[unlisted]	[unknown]
MITSUBISHI					[unlisted]	[unlisted]	A private spam database. You can perform a lookup at http://www.DNSstuff.com.
NERD					*.countries.nerd.dk	Unknown	Lists IPs in certain countries. Missing test entry of 127.0.0.2. Confirmed 18 Jun 2002. Warning: Is not testable.
NETHERRELAYS					relays.nether.net	[unlisted]	Lists mailservers that send to non-existent accounts at nether.net. Zone transfers requested for large use hosts.
NETHERUNSURE					unsure.nether.net	[unlisted]	Lists mailservers that cannot be tested. Zone transfers requested for large use hosts.
NJABL					dnsbl.njabl.org	127.0.0.2	Lists open relays and known spam sources. Test listing confirmed 07 Jan 2002.
NJABLDUL					dnsbl.njabl.org	127.0.0.3	Lists dialup lines and other dynamic IP ranges. NOTE: As with other dialup lists, you should NOT use this to scan mail from your users, if you are an ISP. Test listing confirmed 07 Jan 2002.
NJABLDYNA					dynablock.njabl.org	127.0.0.3	Contains the IPs from the old EASYNET-DYNA test. Unconfirmable as of 23 Dec 2003.
NJABLFORMMAIL					dnsbl.njabl.org	127.0.0.8	Lists servers with insecure formmail scripts. Test listing confirmed 29 Oct 2002.
NJABLMULTI					dnsbl.njabl.org	127.0.0.5	Lists multi-stage open relays. Will notify the appropriate NIC one week in advance of listing, to allow them to correct the problem. Test listing confirmed 29 Oct 2002.
NJABLPROXIES					dnsbl.njabl.org	127.0.0.9	Lists open proxy servers. Test listing confirmed 29 Oct 2002.
NJABLSOURCES					dnsbl.njabl.org	127.0.0.4	Lists spam sources. Will include commercial spammers, direct-to-mx, and proxies. IP ranges will be added only if they can be identified with the spammer. Test listing confirmed 29 Oct 2002.
NLKUNBLACKLIST					blacklist.sci.kun.nl	[unlisted]	Documentation not in English. No TXT records, missing test entry of 127.0.0.2. Warning: Is not testable.
NOFALSENEGATIVE					nofalsenegative.stopspam.samspade.org	[unknown]	Lists every IP address. Primarily for testing purposes.
NOFALSEPOSITIVE					nofalsepositive.stopspam.samspade.org	[unknown]	Lists no IP addresses. Primarily for testing purposes. Technically listed untestable, since it cannot (by design) include the test IP of 127.0.0.2. Warning: Is not testable.
NOMOREFUNN					no-more-funn.moensted.dk	[various]	Undocumented. Will list dialup networks that send spam, and are outside Scandinavia. Lists IPs that send spam or attempt relaying. Also lists networks of Danish spammers. Confirmed 09 Apr 2002.
ORVEDB					orvedb.aupads.org	[unlisted]	Lists hosts that are verified as open relays. No TXT records, missing test entry 127.0.0.2. Warning: Is not testable.
OUTBLAZE					[unlisted]	[unlisted]	local blocklist of known / potential spam source IPs and netblocks, known as the OBSL (OutBlaze Spammers List). This includes known spam sources not otherwise listed in the various DNSBLs we use, as well as open relays which deliver spam.
POSTFIXGATE					bl.redhatgate.com	127.0.0.1	A pay service with a list of mail servers that send spam. Includes TXT records. Verified Nov 28 2001. Warning: Is not testable.
PSBL					psbl.surriel.com	[unknown]	Lists IPs of computers that send spam, while allowing anyone to remove their IP (with the idea that spammers won't bother to try to remove 1000s of IPs). Confirmed 15 Dec 2003.
RANGERSBL					dnsbl.rangers.eu.org	[various]	Lists IPs and IP ranges that send E-mail that is reported as spam, E-mail that is sent to spamtraps, and general spam with public evidence. Does not accept nominations. Was RRBL.
REDHAWK					access.redhawk.org	[unknown]	Unknown. Site currently down. Confirmed 23 Dec 2003.
REGEDIT64					dnsbl.regedit64.net	127.0.0.2	DNS of IP's sending SPAM or Virus emails to our traps. Administrator: abuse@regedit64.net
RSBL					rsbl.aupads.org	[unlisted]	Lists hosts that were verified a true and ostensible spammer activity. Warning: Will list legitimate mailservers that have no reverse DNS entry. No TXT records, missing test entry 127.0.0.2. Warning: Is not testable.
SATOS					satos.rbl.cluecentral.net	[unlisted]	A personal blacklist, that lists IPs of spammers that send to the administrator of cluecentral.net. Warning: Is not testable.
SBL					sbl.spamhaus.org	127.0.0.2	Spamhaus Block List. Lists 'known spammers, spam gangs or spam support services'. Confirmed on 21 Mar 2002.
SBL-XBL					xbl.spamhaus.org	127.0.0.4	SBL Exploits Block List. This contains the same data as the CBL test. Can be combined with SBL by using sbl-xbl.spamhaus.org. Lists IP addresses of exploited servers. Note that this is not the same as the XBL spam test, run by another organization (which is why this needs to be referred to as "SBL-XBL" rather than just "XBL"). Confirmed 14 Jan 2004.
SCHULTE					rbl.schulte.org	[unlisted]	Lists mailservers that the administrator of the schulte.org domain doesn't want to get mail from. No TXT records, missing 127.0.0.2 test entry. Warning: Is not testable.
SDERB					msgid.bl.gweep.ca	[unlisted]	Scary Devil Enterprises Realtime Blocklist. Lists IPs of mailservers that have sent mail to bad addresses on SDE mailservers in the past 2 1/2 hours, that are not in several other spam databases. No TXT records, missing 127.0.0.2 test entry. Warning: Is not testable.
SENDERBASE					query.senderbase.org	[various]	Keeps track of how much E-mail is being sent from IPs/domains, has information about many of them. Keeps interesting information and statistics on IPs. Only uses TXT records, so it requires special support from anti-spam software.
SERVICESNET					korea.services.net	[unknown]	Lists all IPs in South Korea; see URL for details. Unconfirmed 28 Oct 2002 due to no 127.0.0.2 test entry. Warning: Is not testable.
SOLID					dnsbl.solid.net	[unknown]	Not well documented. Confirmed 23 Dec 2003.
SORBS-BLOCK					dnsbl.sorbs.net	127.0.0.8	Spam and Open Relay Blocking System. This test lists networks that request never to be tested. Confirmed on 28 Aug 2003. Can also be used with the zone block.dnsbl.sorbs.net.
SORBS-DUHL					dnsbl.sorbs.net	127.0.0.10	Spam and Open Relay Blocking System. This test lists dynamic IP ranges. Confirmed on 28 Aug 2003. Can also be used with the zone dul.dnsbl.sorbs.net.
SORBS-HTTP					dnsbl.sorbs.net	127.0.0.2	Spam and Open Relay Blocking System. This test lists Open HTTP Proxy servers. Confirmed on 11 Dec 2002. May return multiple A records. Can also be used with the zone http.dnsbl.sorbs.net.
SORBS-MISC					dnsbl.sorbs.net	127.0.0.4	Spam and Open Relay Blocking System. This test lists open proxy servers not listed in the SORBS-HTTP or SORBS-SOCKS tests. Confirmed on 11 Dec 2002. May return multiple A records. Can also be used with the zone misc.dnsbl.sorbs.net.
SORBS-SMTP					dnsbl.sorbs.net	127.0.0.5	Spam and Open Relay Blocking System. This test lists open relays. Confirmed on 11 Dec 2002. May return multiple A records. Can also be used with the zone smtp.dnsbl.sorbs.net.
SORBS-SOCKS					dnsbl.sorbs.net	127.0.0.3	Spam and Open Relay Blocking System. This test lists Open SOCKS Proxy servers. Confirmed on 11 Dec 2002. May return multiple A records. Can also be used with the zone socks.dnsbl.sorbs.net.
SORBS-SPAM					dnsbl.sorbs.net	127.0.0.6	Spam and Open Relay Blocking System. This test lists hosts that have sent spam to the admins of SORBS. Confirmed on 11 Dec 2002. May return multiple A records. Can also be used with the zone spam.dnsbl.sorbs.net.
SORBS-WEB					dnsbl.sorbs.net	127.0.0.7	Spam and Open Relay Blocking System. This test lists web servers which have vulnerabilities that can be used by spammers (such as formmail scripts). Confirmed on 11 Dec 2002. May return multiple A records. Can also be used with the zone web.dnsbl.sorbs.net.
SORBS-ZOMBIE					dnsbl.sorbs.net	127.0.0.9	Spam and Open Relay Blocking System. This test lists networks hijacked from their original owners, some of which are already spamming.. Confirmed on 12 May 2003. Can also be used with the zone zombie.dnsbl.sorbs.net.
SPAMCANNIBAL					bl.spamcannibal.org	127.0.0.2	Lists IPs that have sent spam to the SpamCannibal mailservers. Confirmed 15 Dec 2003.
SPAMCOP					bl.spamcop.net	127.0.0.2	Lists mail servers that have a high spam-to-legitimate-mail ratio. Catches about the most spam of all tests. Donations are requested.
SPAMRBL					map.spam-rbl.com	127.0.0.2	Instructions in French. Test IP is 127.0.0.2 and return is 127.0.0.2 : # host -t A 2.0.0.127.map.spam-rbl.com 2.0.0.127.map.spam-rbl.com has address 127.0.0.2 # host -t TXT 2.0.0.127.map.spam-rbl.com 2.0.0.127.map.spam-rbl.com text "Blacklist TEST IP"
SPAMSOURCES					spamsoures.dnsbl.info	[unknown]	Undocumented. Untestable as of 23 Dec 2003. Warning: Is not testable.
TECHNOVISION					bl.technovision.dk	[various]	Lists IPs of mailservers that have sent spam to the administrator of technovision.dk.
TRIUMF					rbl.triumf.ca	127.0.0.2	Lists open relays that send E-mail to the triumf.ca domain. Unconfirmable on 09 Apr 2002. Warning: Is not testable.
TUBERLIN					rblmap.tu-berlin.de	[unknown]	Unconfirmable on 09 Apr 2002. No documentation. Warning: Is not testable.
UCEPROTECTL1					dnsbl-1.uceprotect.net	127.0.0.2	Lists IPs that have sent spam, that have no reverse DNS or are dialups or are open proxies or open relays. Confirmed 04 Jan 2004. .
UCEPROTECTL2					dnsbl-2.uceprotect.net	127.0.0.2	Lists Class C IP ranges that have sent spam from more than one IP. Confirmed 04 Jan 2004.
UCEPROTECTL3					dnsbl-3.uceprotect.net	127.0.0.2	Lists Class C IP ranges if a single IP in the range sends out a virus. Confirmed 04 Jan 2004.
US					*.blackholes.us	127.0.0.2	Lists IPs of about 20 different countries and many ISPs (one zone per country/ISP), including Verio. Confirmed 23 Aug 2002. Warning: Is not testable.
VIRBL					virbl.dnsbl.bit.nl	[unknown]	Lists IPs that are known to be infected by viruses. Confirmed on 08 June 2004.
WPBL					db.wpbl.info	127.0.0.2	Private. Automated distributed spam detection using statistical (mostly bayesian) filters. Uses both spam and non-spam sightings. Blocks automatically expire with time, and IPs can be instantly removed through a web form.
WSFF					will-spam-for-food.eu.org	[unknown]	Unconfirmable on 09 Apr 2002. No documentation. Warning: Is not testable.
WYTNIJ					spam.wytnij.to	[Unknown]	Looks like a valid spam database, but untestable (on 24 Mar 2002). Instruction appear to be in Polish, although it's a Tonga domain. Warning: Is not testable.
YBL					ybl.megacity.org	127.0.0.2	Lists all known Yahoo (and subsidiaries) netblocks, worldwide. Confirmed on 01 Jun 2002.
ZONEEDIT					[unknown]	[unknown]	Undocumented. Untestable as of 23 Dec 2003. Warning: Is not testable.

Name/link	A	TXT	Free	OK	Lookup Domain	Returns	Description
AHBL-RHSBL					rhsbl.ahbl.org	[various]	Abusive Hosts Blocking List. This is the RHSBL version, which lists domains from the return addresses of spams. Lists domains owned by known spammers, used exclusively by spammers, and domains which should never be used in the From: address in E-mails (such as domains that offered free E-mail but were closed down years ago).
BADWHOIS					whois.rfc-ignorant.org	[various]	Lists domains that have incorrect or otherwise bad information in their whois data. Returns 127.0.0.7 for a TLD that is listed (IE .uk), or 127.0.0.5 for an individual domain.
BGISOCBL					dnsbl.isoc.bg	[unlisted]	Bulgarian Spam Prevention System. Designed primarily to protect isoc.bg's members from receiving Bulgarian spam. Warning: Is not testable.
BOGUSMX					bogusmx.rfc-ignorant.org	127.0.0.8	Lists domains that have bogus MX records (pointing to bogus IPs, hostnames with no A records, or MX pointing to an IP rather than a hostname).
CART00NEY					cart00ney.surriel.com	[127.0.0.2]	Lists domains of spammers that have sent 'cart00ney threats', typically to people who operate spam databases. Confirmed 26 Jan 2004.
DEADBEEF					bl.deadbeef.com	127.0.0.2	Lists ISPs that have no way to report abuse. Missing example.com test entry.
DNSBLNETAUENDN					endn.dnsbl.net.au	[Unknown]	Reynolds EasyNet Domain Names List. Contains the Easynet Spamlist, filtered to only contain domain names, and exclude all the email addresses on that list. Free for first 1,000 lookups per day. Confirmed 11 Sep 2003.
DNSFRAUD					in.dnsbl.org	127.0.0.3	Lists domains that used credit card or wire fraud to obtain services. Does not include test 'example.com' address, and no TXT records, but verified to be working on 10 Dec 2001.
DNSILLEGAL					in.dnsbl.org	127.0.0.5	Lists domains that offer illegal content. Does not include test 'example.com' address, and no TXT records, but verified to be working on 10 Dec 2001.
DNSMAILLIST					in.dnsbl.org	127.0.0.6	Lists domains that use improper mailing list practices. Does not include test 'example.com' address, and no TXT records, but verified to be working on 10 Dec 2001.
DNSPROMO					in.dnsbl.org	127.0.0.4	Lists domains that promote spam software. Does not include test 'example.com' address, and no TXT records, but verified to be working on 10 Dec 2001.
DNSUCE					in.dnsbl.org	127.0.0.2	Lists domains that are known to send UCE (designed for DNS providers). Does not include test 'example.com' address, and no TXT records, but verified to be working on 10 Dec 2001.
DSN					dsn.rfc-ignorant.org	127.0.0.2	Lists domains that do not accept Delivery Status Notifications (DSNs), such as bounce messages.
DUHLUSERS					duhlusers.yamta.org	127.0.0.2	Lists domains that block E-mail based on any dynamic IP or dial-up pool list. This RHSBL will likely list major domains, which can cause false positives. Confirmed 07 Apr 2004.
EXDNSBL					ex.dnsbl.org	[various]	Lists domains listed at spamsites.org (127.0.0.2), and domains banned from easyDNS mailhubs (127.0.0.3). Does not include test 'example.com' address, therefore unconfirmed 28 Oct 2002. Warning: Is not testable.
MAILPOLICE-BULK					bulk.rhs.mailpolice.com	127.0.0.2	A list of domains that have been used in spam (in the MAIL FROM or an advertised URL), that are not porn related. Also can be accessed via block.rhs.mailpolice.com, which includes all MAILPOLICE tests.
MAILPOLICE-PORN					porn.rhs.mailpolice.com	127.0.0.2	A list of domains that have been used in spam (in the MAIL FROM or an advertised URL), that are porn related. Also can be accessed via block.rhs.mailpolice.com, which includes all MAILPOLICE tests.
NOABUSE					abuse.rfc-ignorant.org	127.0.0.4	Lists domains that do not accept E-mail to abuse@. Includes some popular domains.
NOPOSTMASTER					postmaster.rfc-ignorant.org	127.0.0.3	Lists domains that do not accept E-mail to postmaster@. Includes some popular domains.
SECURITYSAGE					blackhole.securitysage.com	127.0.0.5	Lists domains that meet one of numerous criteria (see their site for details).
SORBS-BADCONF					rhsbl.sorbs.net	127.0.0.11	Spam and Open Relay Blocking System. This test lists domains whose MX or A records point to bad address space. Confirmed on 28 Aug 2003. Can also be used with the zone badconf.dnsbl.sorbs.net.
SORBS-NOMAIL					rhsbl.sorbs.net	127.0.0.12	Spam and Open Relay Blocking System. This test lists domains where the owners say that no mail should be sent from the domains. Confirmed on 28 Aug 2003. Can also be used with the zone nomail.dnsbl.sorbs.net.

Name/link	A	TXT	Free	OK	Lookup Domain	Returns	Description
PTR						[n/a]	Reverse DNS entry. Not a standard DNS-based spam test. Warning: Is not testable.
DNSBLNETAURDDN					rddn.dnsbl.net.au	[Unknown]	Reynolds Dynamic Domain Names List. Contains a collection of domain named hosts which are normally assigned dynamically. Used with reverse DNS entries. Free for first 1,000 lookups per day. Confirmed 11 Sep 2003.
LTAMS					openlists.orbs.org	[various]	List Tracking and Monitoring System. Lists open mailing list output points. This list exists and is updated, but currently has no home (zone) as of 09 Apr 2002. Warning: Is not testable.

Name/link	A	TXT	Free	OK	Lookup Domain	Returns	Description
AOL					[n/a]	[n/a]	Although AOL does have its own open relay database, it does NOT make it publicly available. Warning: Is not testable.
BRAINERD					blackholes.brainerd.net	[unknown]	Hand lists sites that send large amounts of spam. Appears to be a private database; listed here for completeness. Warning: Is not testable.
DRBL					[n/a]	[n/a]	Distributed Realtime Black List. A distributed system, essentially a list of blacklists run by individual companies and private users.
SNIFFER					[n/a]	[n/a]	This is not a DNS spam database, and does charge a modest fee. However, it can be used in conjunction with most server-based spam control programs. It is very effective, and complements IP-based spam tests very well, as it examines the content of E-mail rather than the source. Warning: Is not testable.

BGISOCWL					dnswl.isoc.bg	[unlisted]	Bulgarian Spam Prevention System Whitelist. Designed primarily to protect isoc.bg's members from receiving Bulgarian spam; this is a WHITELIST, which lists 'good' IPs. No TXT records, missing test entry 127.0.0.2. Warning: Is not testable.
HABEAS					[n/a]	[n/a]	A unique approach to false positives, based on using existing intellectual property laws to automatically whitelist E-mail from legitimate senders using the 'Habeas headers' (a copyrighted haiku and a trademark), while spammers cannot legally use them. Warning: Is not testable.
HOSTKARMA					hostkarma.junkemailfilter.com	127.0.01	Free DNS host karma listing servers to provide information to the world about what servers are sending spam, nonspam, or a mix of spam and nonspam. This is a service of http://www.junkemailfilter.com one of many technologies used in advanced email filtering.
HUL					[Unlisted]	[unknown]	Lists IPs of Habeas licensees. Used as a whitelist. Requires a license agreement to be filled out. Warning: Is not testable.
IADB					[Unlisted]	[various]	Email Senders Accreditation program available to email marketers and email senders.
NLKUNWHITELIST					whitelist.sci.kun.nl	[unlisted]	Documentation not in English. Apparently a whitelist. No TXT records, missing test entry of 127.0.0.2. Warning: Is not testable.
SENDERSCORE					query.bondedsender.org	127.0.0.10	Sender Score Certified, a whitelist of E-mail senders who adhere to extremely strict program standards for upstanding, legitimate email behavior. These standards are driven by comprehensive reputation monitoring data available from the Sender Score Network. Previously known as BONDEDSENDER