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	113,138
this-domain-for-sale.com	128.121.3.72	113,128
dns1.name-services.com	63.251.163.102	94,722
dns2.name-services.com	216.52.184.230	94,717
dns3.name-services.com	63.251.83.36	94,698
dns4.name-services.com	64.74.96.242	94,669
dns5.name-services.com	212.118.244.163	94,286
a.ns.interland.net	64.226.28.33	50,728
b.ns.interland.net	69.0.145.33	50,703
c.ns.interland.net	64.77.127.42	50,524
ns1.directnic.com	206.251.177.2	48,436
ns0.directnic.com	204.251.10.100	48,314
ns8.san.yahoo.com	66.218.71.205	47,533
ns9.san.yahoo.com	216.109.116.20	47,532
ns2.ultsearch.com	212.100.230.160	45,257
ns1.ultsearch.com	213.130.63.232	45,257
ns.schlund.de	195.20.224.97	44,770
yns1.yahoo.com	66.218.71.205	44,668
yns2.yahoo.com	216.109.116.20	44,666
ns1.secure.net	192.220.124.10	42,922

Survey Limitations

Our survey, while having an impressive 14,500,417 sites and 8,243,805 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).