GRC's DNS Benchmark performs a detailed analysis and comparison of
the operational performance and reliability of any set of up to 200 DNS nameservers (sometimes also called resolvers)
at once. When the Benchmark is started in its default configuration, it
identifies all DNS nameservers the user's system is currently
configured to use and adds them to its built-in list of publicly
available “alternative” nameservers. Each DNS nameserver in the
benchmark list is carefully “characterized” to determine its suitability
— to you — for your use as a DNS resolver. This characterization
includes testing each nameserver for its “redirection” behavior: whether
it returns an error for a bad domain request, or redirects a user's web
browser to a commercial marketing-oriented page. While such behavior
may be acceptable to some users, others may find this objectionable.