This report details the names and locations of all DNS servers on the internet, as well as the number of domains that are serviced by these servers. In this fashion, we can discover

• the number of sites hosted by ISPs
• the number of sites hosted by hosting companies that use an ISP's facilities, but run their own name servers
• the number of sites hosted by specialty DNS service providers
• the organizations that choose to operate their own DNS servers rather than to use those of their ISP/hosting provider.

The survey works by determining each month the authoritative name server for each host (and more accurately, each domain) in our survey. We then count the number of domains hosted on each DNS server.

Search

Curious about the size of a the domain set handled by a particular ISP's name servers? Try searching for the ISP's name server. For example, to find Exodus' name servers, try exodus.

Top 20 by Host Name

The top 20 name servers ranked according to the number of domains handled by each name server, with a name server uniquely identified by its fully qualifed name, are shown below.

Name Server Name	Name Server IP	Domains
dns2.name-services.com	216.52.184.248	269,159
dns1.name-services.com	69.25.142.42	269,156
dns4.name-services.com	69.64.145.225	269,030
dns3.name-services.com	63.251.92.200	268,994
dns5.name-services.com	70.42.37.7	267,594
yns1.yahoo.com	66.218.71.205	164,645
yns2.yahoo.com	216.109.116.20	164,643
ns8.san.yahoo.com	66.218.71.205	164,606
ns9.san.yahoo.com	216.109.116.20	164,605
ns1.dreamhost.com	66.33.206.206	156,213
ns2.dreamhost.com	208.96.10.221	156,187
ns3.dreamhost.com	66.33.216.216	155,140
dns2.technorail.com	62.149.132.2	150,034
dns.technorail.com	62.149.128.2	150,031
ns02.domaincontrol.com	208.109.255.1	96,551
ns01.domaincontrol.com	64.202.165.4	96,505
ns2.rackspace.com	65.61.188.4	89,969
ns.rackspace.com	69.20.95.4	89,946
ns1.livedns.co.uk	213.171.192.250	88,882
ns2.livedns.co.uk	213.171.193.250	88,878

Survey Limitations

Our survey, while having an impressive 34,895,892 sites and 17,674,086 domains in the data set, does not include all web sites and domains. We only include those that we consider active, which, by our definition, means we found the site via a link from somewhere else. Sites not linked by anyone are by definition not included in the survey.

We also actively drop sites out of the survey that fail to respond 3 consecutive months to our HTTP queries. So, while a DNS server might still respond with information for a domain, if there is no active web site that we can reach for the domain in question, then the domain is not included in this survey at all, even if it still has other functioning services (such as email).