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
ns.buydomains.com	208.254.3.177	100,768
ns2.buydomains.com	128.121.3.74	100,630
a.ns.interland.net	64.226.28.33	46,394
b.ns.interland.net	66.111.73.173	46,376
c.ns.interland.net	64.77.127.42	46,204
ns1.secure.net	192.220.124.10	32,419
ns2.secure.net	192.220.125.10	32,399
dns2.nic.it	193.205.245.8	31,132
ns1.mydomain.com	216.52.121.227	30,874
ns2.mydomain.com	216.52.121.234	30,869
ns3.mydomain.com	216.34.94.182	30,848
ns4.mydomain.com	216.52.121.235	30,837
dns3.name-services.com	63.251.83.36	30,172
dns4.name-services.com	216.89.126.2	30,172
dns5.name-services.com	63.251.83.37	30,168
dns2.name-services.com	66.216.126.143	30,166
dns1.name-services.com	66.150.5.103	30,166
dns2.earthlink.net	207.217.77.12	28,847
dns3.earthlink.net	207.217.120.13	28,840
dns1.earthlink.net	207.217.126.11	28,832

Survey Limitations

Our survey, while having an impressive 8,952,157 sites and 5,322,729 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).