ViewDNS.info - Free DNS related tools including Reverse IP Lookup, DNS Propagation Checker, Chinese Firewall Test...

Site Rank Data - View historical rank information of websites via time series charts.

Whats My DNS - Instantly check your domain names current IP address and DNS record information against multiple name servers located in different parts of the world.

AdClarity - Optimize Display Advertising campaigns with the AdClarity Marketing Intelligence Tool for Advertisers, Agencies, Publishers, Ad Networks,

NsLookup.io - A simple and powerful tool for querying DNS records

Quantcast - Quantcast Corporation is a digital marketing company that provides free audience demographics measurement and delivers real-time advertising.