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
dns01.exodus.net	209.1.222.244	4,586
dns02.exodus.net	209.1.222.245	4,530
dns03.exodus.net	209.1.222.246	4,490
dns04.exodus.net	209.1.222.247	4,439
sca02.sec.dns.exodus.net	209.1.235.120	751
sca03.auth.dns.exodus.net	209.185.253.230	446
sca04.auth.dns.exodus.net	216.32.104.10	445
sca03.sec.dns.exodus.net	216.32.126.150	150
exodus.hipdesign.com	63.236.10.61	103
exodus.exodustech.com	216.214.52.130	45
ns3.exodus.net	206.79.240.13	25
exodus.ssmnet.net	24.123.118.150	22
wlhm02sdns01.exodus.net	64.28.79.26	21
sntc04sdns01.exodus.net	64.14.1.122	20
pdns01.lndn01.exodus.net	212.62.1.87	20
ns2.nj.exodus.net	209.1.10.234	19
ns2.exodus.net	207.82.198.150	17
ns.exodus.net	206.79.230.10	17
exodus.theworldat.com	209.101.130.4	16
exodus.micro-net.net	207.182.64.2	16

Survey Limitations

Our survey, while having an impressive 11,046,645 sites and 6,833,381 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).