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
ns1.bluehost.com	74.220.195.31	467,120
ns2.bluehost.com	69.89.16.4	467,107
f1g1ns1.dnspod.net	113.108.80.138	452,459
f1g1ns2.dnspod.net	112.90.82.194	451,720
ns1.dreamhost.com	66.33.206.206	371,386
ns2.dreamhost.com	208.97.182.10	371,365
ns3.dreamhost.com	66.33.216.216	371,019
dns.technorail.com	62.149.128.2	329,646
dns2.technorail.com	62.149.132.2	329,644
dns3.arubadns.net	95.110.220.5	328,985
dns4.arubadns.cz	81.2.199.73	328,983
dns2.name-services.com	98.124.197.1	320,868
dns1.name-services.com	98.124.192.1	320,852
dns3.name-services.com	98.124.193.1	320,850
dns4.name-services.com	98.124.194.1	320,557
dns5.name-services.com	98.124.196.1	319,390
ns1.dns.ne.jp	210.188.224.9	277,282
ns2.dns.ne.jp	210.224.172.13	277,233
ns1.51dns.com	121.12.104.18	247,141
ns2.51dns.com	121.12.104.22	247,140

Survey Limitations

Our survey, while having an impressive 95,187,240 sites and 37,022,198 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).