Reputation monitoring sites

There are a number of sites online that provide public information about reputation of an IP address or domain name.

1. Sender Score – http://senderscore.org/. Provided by Return Path. They collect data from some ISPs and blocklists. Using a proprietary formula, they calculate a sender score running from 1 – 100 for each IP address sending mail to their network. Higher scores means a better reputation. Can be inaccurate for IPs sending very low volumes of email. Some ISPs use Sender Score to feed into their delivery decision engines.
2. Sender Base – http://senderbase.org/. Provided by Ironport / Cisco. They collect publicly available data as well as data from their userbase. Reputation is reported as “good” “poor” or “neutral.” Senderbase scores feed into some ISP delivery decision engines.
3. AOL reputation – http://postmaster.aol.com/cgi-bin/plugh/check_ip.pl. Reports the reputation of IPs as determined by AOL. Uses a scale of “good” “poor” or “neutral”.
4. RoadRunner blocks – http://security.rr.com/amIBlockedByRR. Reports if a particular IP address is currently being blocked from sending mail to Road Runner.
5. Spamhaus blocks – http://www.spamhaus.org/. Reports if an IP is currently listed on any of the Spamhaus lists.
6. Sendmail Reputation – http://sendmail.com/sm/resources/tools/ip_reputation/. Reports reputation of an IP address as measured by Sendmail.
7. Trusted Source – http://www.trustedsource.org/. Provided by McAfee.
8. Commtouch – http://www.commtouch.com/check-ip-reputation/. Provided by Commtouch.
9. Barracuda Central – http://www.barracudacentral.org/lookups/. Provided by Barracuda, shows what IP addresses or domain names are currently blocked.
10. SNDS – http://postmaster.live.com/snds/. Provided by Microsoft / Hotmail / Live.com. Will show IP addresses that are currently blocked by Microsoft.